Metamath Proof Explorer


Theorem sat1el2xp

Description: The first component of an element of the value of the satisfaction predicate as function over wff codes in the empty model with an empty binary relation is a member of a doubled Cartesian product. (Contributed by AV, 17-Sep-2023)

Ref Expression
Assertion sat1el2xp N ω w Sat N a b 1 st w ω × a × b

Proof

Step Hyp Ref Expression
1 fveq2 x = Sat x = Sat
2 1 raleqdv x = w Sat x a b 1 st w ω × a × b w Sat a b 1 st w ω × a × b
3 fveq2 x = y Sat x = Sat y
4 3 raleqdv x = y w Sat x a b 1 st w ω × a × b w Sat y a b 1 st w ω × a × b
5 fveq2 x = suc y Sat x = Sat suc y
6 5 raleqdv x = suc y w Sat x a b 1 st w ω × a × b w Sat suc y a b 1 st w ω × a × b
7 fveq2 x = N Sat x = Sat N
8 7 raleqdv x = N w Sat x a b 1 st w ω × a × b w Sat N a b 1 st w ω × a × b
9 eqeq1 x = 1 st w x = i 𝑔 j 1 st w = i 𝑔 j
10 9 2rexbidv x = 1 st w i ω j ω x = i 𝑔 j i ω j ω 1 st w = i 𝑔 j
11 10 anbi2d x = 1 st w z = i ω j ω x = i 𝑔 j z = i ω j ω 1 st w = i 𝑔 j
12 eqeq1 z = 2 nd w z = 2 nd w =
13 12 anbi1d z = 2 nd w z = i ω j ω 1 st w = i 𝑔 j 2 nd w = i ω j ω 1 st w = i 𝑔 j
14 11 13 elopabi w x z | z = i ω j ω x = i 𝑔 j 2 nd w = i ω j ω 1 st w = i 𝑔 j
15 goel i ω j ω i 𝑔 j = i j
16 15 eqeq2d i ω j ω 1 st w = i 𝑔 j 1 st w = i j
17 omex ω V
18 17 17 pm3.2i ω V ω V
19 peano1 ω
20 19 a1i i ω j ω ω
21 opelxpi i ω j ω i j ω × ω
22 20 21 opelxpd i ω j ω i j ω × ω × ω
23 xpeq12 a = ω b = ω a × b = ω × ω
24 23 xpeq2d a = ω b = ω ω × a × b = ω × ω × ω
25 24 eleq2d a = ω b = ω i j ω × a × b i j ω × ω × ω
26 25 spc2egv ω V ω V i j ω × ω × ω a b i j ω × a × b
27 18 22 26 mpsyl i ω j ω a b i j ω × a × b
28 eleq1 1 st w = i j 1 st w ω × a × b i j ω × a × b
29 28 2exbidv 1 st w = i j a b 1 st w ω × a × b a b i j ω × a × b
30 27 29 syl5ibrcom i ω j ω 1 st w = i j a b 1 st w ω × a × b
31 16 30 sylbid i ω j ω 1 st w = i 𝑔 j a b 1 st w ω × a × b
32 31 rexlimivv i ω j ω 1 st w = i 𝑔 j a b 1 st w ω × a × b
33 32 adantl 2 nd w = i ω j ω 1 st w = i 𝑔 j a b 1 st w ω × a × b
34 14 33 syl w x z | z = i ω j ω x = i 𝑔 j a b 1 st w ω × a × b
35 satf00 Sat = x z | z = i ω j ω x = i 𝑔 j
36 34 35 eleq2s w Sat a b 1 st w ω × a × b
37 36 rgen w Sat a b 1 st w ω × a × b
38 omsucelsucb y ω suc y suc ω
39 satf0sucom suc y suc ω Sat suc y = rec f V f x z | z = u f v f x = 1 st u 𝑔 1 st v i ω x = 𝑔 i 1 st u x z | z = i ω j ω x = i 𝑔 j suc y
40 38 39 sylbi y ω Sat suc y = rec f V f x z | z = u f v f x = 1 st u 𝑔 1 st v i ω x = 𝑔 i 1 st u x z | z = i ω j ω x = i 𝑔 j suc y
41 40 adantr y ω w Sat y a b 1 st w ω × a × b Sat suc y = rec f V f x z | z = u f v f x = 1 st u 𝑔 1 st v i ω x = 𝑔 i 1 st u x z | z = i ω j ω x = i 𝑔 j suc y
42 nnon y ω y On
43 rdgsuc y On rec f V f x z | z = u f v f x = 1 st u 𝑔 1 st v i ω x = 𝑔 i 1 st u x z | z = i ω j ω x = i 𝑔 j suc y = f V f x z | z = u f v f x = 1 st u 𝑔 1 st v i ω x = 𝑔 i 1 st u rec f V f x z | z = u f v f x = 1 st u 𝑔 1 st v i ω x = 𝑔 i 1 st u x z | z = i ω j ω x = i 𝑔 j y
44 42 43 syl y ω rec f V f x z | z = u f v f x = 1 st u 𝑔 1 st v i ω x = 𝑔 i 1 st u x z | z = i ω j ω x = i 𝑔 j suc y = f V f x z | z = u f v f x = 1 st u 𝑔 1 st v i ω x = 𝑔 i 1 st u rec f V f x z | z = u f v f x = 1 st u 𝑔 1 st v i ω x = 𝑔 i 1 st u x z | z = i ω j ω x = i 𝑔 j y
45 44 adantr y ω w Sat y a b 1 st w ω × a × b rec f V f x z | z = u f v f x = 1 st u 𝑔 1 st v i ω x = 𝑔 i 1 st u x z | z = i ω j ω x = i 𝑔 j suc y = f V f x z | z = u f v f x = 1 st u 𝑔 1 st v i ω x = 𝑔 i 1 st u rec f V f x z | z = u f v f x = 1 st u 𝑔 1 st v i ω x = 𝑔 i 1 st u x z | z = i ω j ω x = i 𝑔 j y
46 elelsuc y ω y suc ω
47 satf0sucom y suc ω Sat y = rec f V f x z | z = u f v f x = 1 st u 𝑔 1 st v i ω x = 𝑔 i 1 st u x z | z = i ω j ω x = i 𝑔 j y
48 46 47 syl y ω Sat y = rec f V f x z | z = u f v f x = 1 st u 𝑔 1 st v i ω x = 𝑔 i 1 st u x z | z = i ω j ω x = i 𝑔 j y
49 48 eqcomd y ω rec f V f x z | z = u f v f x = 1 st u 𝑔 1 st v i ω x = 𝑔 i 1 st u x z | z = i ω j ω x = i 𝑔 j y = Sat y
50 49 fveq2d y ω f V f x z | z = u f v f x = 1 st u 𝑔 1 st v i ω x = 𝑔 i 1 st u rec f V f x z | z = u f v f x = 1 st u 𝑔 1 st v i ω x = 𝑔 i 1 st u x z | z = i ω j ω x = i 𝑔 j y = f V f x z | z = u f v f x = 1 st u 𝑔 1 st v i ω x = 𝑔 i 1 st u Sat y
51 50 adantr y ω w Sat y a b 1 st w ω × a × b f V f x z | z = u f v f x = 1 st u 𝑔 1 st v i ω x = 𝑔 i 1 st u rec f V f x z | z = u f v f x = 1 st u 𝑔 1 st v i ω x = 𝑔 i 1 st u x z | z = i ω j ω x = i 𝑔 j y = f V f x z | z = u f v f x = 1 st u 𝑔 1 st v i ω x = 𝑔 i 1 st u Sat y
52 eqidd y ω w Sat y a b 1 st w ω × a × b f V f x z | z = u f v f x = 1 st u 𝑔 1 st v i ω x = 𝑔 i 1 st u = f V f x z | z = u f v f x = 1 st u 𝑔 1 st v i ω x = 𝑔 i 1 st u
53 id f = Sat y f = Sat y
54 rexeq f = Sat y v f x = 1 st u 𝑔 1 st v v Sat y x = 1 st u 𝑔 1 st v
55 54 orbi1d f = Sat y v f x = 1 st u 𝑔 1 st v i ω x = 𝑔 i 1 st u v Sat y x = 1 st u 𝑔 1 st v i ω x = 𝑔 i 1 st u
56 55 rexeqbi1dv f = Sat y u f v f x = 1 st u 𝑔 1 st v i ω x = 𝑔 i 1 st u u Sat y v Sat y x = 1 st u 𝑔 1 st v i ω x = 𝑔 i 1 st u
57 56 anbi2d f = Sat y z = u f v f x = 1 st u 𝑔 1 st v i ω x = 𝑔 i 1 st u z = u Sat y v Sat y x = 1 st u 𝑔 1 st v i ω x = 𝑔 i 1 st u
58 57 opabbidv f = Sat y x z | z = u f v f x = 1 st u 𝑔 1 st v i ω x = 𝑔 i 1 st u = x z | z = u Sat y v Sat y x = 1 st u 𝑔 1 st v i ω x = 𝑔 i 1 st u
59 53 58 uneq12d f = Sat y f x z | z = u f v f x = 1 st u 𝑔 1 st v i ω x = 𝑔 i 1 st u = Sat y x z | z = u Sat y v Sat y x = 1 st u 𝑔 1 st v i ω x = 𝑔 i 1 st u
60 59 adantl y ω w Sat y a b 1 st w ω × a × b f = Sat y f x z | z = u f v f x = 1 st u 𝑔 1 st v i ω x = 𝑔 i 1 st u = Sat y x z | z = u Sat y v Sat y x = 1 st u 𝑔 1 st v i ω x = 𝑔 i 1 st u
61 fvexd y ω w Sat y a b 1 st w ω × a × b Sat y V
62 17 a1i y ω w Sat y a b 1 st w ω × a × b ω V
63 satf0suclem Sat y V Sat y V ω V x z | z = u Sat y v Sat y x = 1 st u 𝑔 1 st v i ω x = 𝑔 i 1 st u V
64 61 61 62 63 syl3anc y ω w Sat y a b 1 st w ω × a × b x z | z = u Sat y v Sat y x = 1 st u 𝑔 1 st v i ω x = 𝑔 i 1 st u V
65 unexg Sat y V x z | z = u Sat y v Sat y x = 1 st u 𝑔 1 st v i ω x = 𝑔 i 1 st u V Sat y x z | z = u Sat y v Sat y x = 1 st u 𝑔 1 st v i ω x = 𝑔 i 1 st u V
66 61 64 65 syl2anc y ω w Sat y a b 1 st w ω × a × b Sat y x z | z = u Sat y v Sat y x = 1 st u 𝑔 1 st v i ω x = 𝑔 i 1 st u V
67 52 60 61 66 fvmptd y ω w Sat y a b 1 st w ω × a × b f V f x z | z = u f v f x = 1 st u 𝑔 1 st v i ω x = 𝑔 i 1 st u Sat y = Sat y x z | z = u Sat y v Sat y x = 1 st u 𝑔 1 st v i ω x = 𝑔 i 1 st u
68 45 51 67 3eqtrd y ω w Sat y a b 1 st w ω × a × b rec f V f x z | z = u f v f x = 1 st u 𝑔 1 st v i ω x = 𝑔 i 1 st u x z | z = i ω j ω x = i 𝑔 j suc y = Sat y x z | z = u Sat y v Sat y x = 1 st u 𝑔 1 st v i ω x = 𝑔 i 1 st u
69 41 68 eqtrd y ω w Sat y a b 1 st w ω × a × b Sat suc y = Sat y x z | z = u Sat y v Sat y x = 1 st u 𝑔 1 st v i ω x = 𝑔 i 1 st u
70 69 eleq2d y ω w Sat y a b 1 st w ω × a × b t Sat suc y t Sat y x z | z = u Sat y v Sat y x = 1 st u 𝑔 1 st v i ω x = 𝑔 i 1 st u
71 elun t Sat y x z | z = u Sat y v Sat y x = 1 st u 𝑔 1 st v i ω x = 𝑔 i 1 st u t Sat y t x z | z = u Sat y v Sat y x = 1 st u 𝑔 1 st v i ω x = 𝑔 i 1 st u
72 70 71 bitrdi y ω w Sat y a b 1 st w ω × a × b t Sat suc y t Sat y t x z | z = u Sat y v Sat y x = 1 st u 𝑔 1 st v i ω x = 𝑔 i 1 st u
73 fveq2 w = t 1 st w = 1 st t
74 73 eleq1d w = t 1 st w ω × a × b 1 st t ω × a × b
75 74 2exbidv w = t a b 1 st w ω × a × b a b 1 st t ω × a × b
76 75 rspccv w Sat y a b 1 st w ω × a × b t Sat y a b 1 st t ω × a × b
77 76 adantl y ω w Sat y a b 1 st w ω × a × b t Sat y a b 1 st t ω × a × b
78 fveq2 w = v 1 st w = 1 st v
79 78 eleq1d w = v 1 st w ω × a × b 1 st v ω × a × b
80 79 2exbidv w = v a b 1 st w ω × a × b a b 1 st v ω × a × b
81 80 rspcva v Sat y w Sat y a b 1 st w ω × a × b a b 1 st v ω × a × b
82 sels 1 st v ω × a × b s 1 st v s
83 82 exlimivv a b 1 st v ω × a × b s 1 st v s
84 81 83 syl v Sat y w Sat y a b 1 st w ω × a × b s 1 st v s
85 84 expcom w Sat y a b 1 st w ω × a × b v Sat y s 1 st v s
86 fveq2 w = u 1 st w = 1 st u
87 86 eleq1d w = u 1 st w ω × a × b 1 st u ω × a × b
88 87 2exbidv w = u a b 1 st w ω × a × b a b 1 st u ω × a × b
89 88 rspcva u Sat y w Sat y a b 1 st w ω × a × b a b 1 st u ω × a × b
90 sels 1 st u ω × a × b s 1 st u s
91 90 exlimivv a b 1 st u ω × a × b s 1 st u s
92 89 91 syl u Sat y w Sat y a b 1 st w ω × a × b s 1 st u s
93 eleq2w s = r 1 st u s 1 st u r
94 93 cbvexvw s 1 st u s r 1 st u r
95 vex r V
96 vex s V
97 95 96 pm3.2i r V s V
98 df-ov 1 st u 𝑔 1 st v = 𝑔 1 st u 1 st v
99 df-gona 𝑔 = e V × V 1 𝑜 e
100 opeq2 e = 1 st u 1 st v 1 𝑜 e = 1 𝑜 1 st u 1 st v
101 opelvvg 1 st u r 1 st v s 1 st u 1 st v V × V
102 opex 1 𝑜 1 st u 1 st v V
103 102 a1i 1 st u r 1 st v s 1 𝑜 1 st u 1 st v V
104 99 100 101 103 fvmptd3 1 st u r 1 st v s 𝑔 1 st u 1 st v = 1 𝑜 1 st u 1 st v
105 98 104 syl5eq 1 st u r 1 st v s 1 st u 𝑔 1 st v = 1 𝑜 1 st u 1 st v
106 1onn 1 𝑜 ω
107 106 a1i 1 st u r 1 st v s 1 𝑜 ω
108 opelxpi 1 st u r 1 st v s 1 st u 1 st v r × s
109 107 108 opelxpd 1 st u r 1 st v s 1 𝑜 1 st u 1 st v ω × r × s
110 105 109 eqeltrd 1 st u r 1 st v s 1 st u 𝑔 1 st v ω × r × s
111 xpeq12 a = r b = s a × b = r × s
112 111 xpeq2d a = r b = s ω × a × b = ω × r × s
113 112 eleq2d a = r b = s 1 st u 𝑔 1 st v ω × a × b 1 st u 𝑔 1 st v ω × r × s
114 113 spc2egv r V s V 1 st u 𝑔 1 st v ω × r × s a b 1 st u 𝑔 1 st v ω × a × b
115 97 110 114 mpsyl 1 st u r 1 st v s a b 1 st u 𝑔 1 st v ω × a × b
116 eleq1 1 st t = 1 st u 𝑔 1 st v 1 st t ω × a × b 1 st u 𝑔 1 st v ω × a × b
117 116 2exbidv 1 st t = 1 st u 𝑔 1 st v a b 1 st t ω × a × b a b 1 st u 𝑔 1 st v ω × a × b
118 115 117 syl5ibrcom 1 st u r 1 st v s 1 st t = 1 st u 𝑔 1 st v a b 1 st t ω × a × b
119 118 ex 1 st u r 1 st v s 1 st t = 1 st u 𝑔 1 st v a b 1 st t ω × a × b
120 119 exlimdv 1 st u r s 1 st v s 1 st t = 1 st u 𝑔 1 st v a b 1 st t ω × a × b
121 120 com23 1 st u r 1 st t = 1 st u 𝑔 1 st v s 1 st v s a b 1 st t ω × a × b
122 121 exlimiv r 1 st u r 1 st t = 1 st u 𝑔 1 st v s 1 st v s a b 1 st t ω × a × b
123 94 122 sylbi s 1 st u s 1 st t = 1 st u 𝑔 1 st v s 1 st v s a b 1 st t ω × a × b
124 92 123 syl u Sat y w Sat y a b 1 st w ω × a × b 1 st t = 1 st u 𝑔 1 st v s 1 st v s a b 1 st t ω × a × b
125 124 expcom w Sat y a b 1 st w ω × a × b u Sat y 1 st t = 1 st u 𝑔 1 st v s 1 st v s a b 1 st t ω × a × b
126 125 com24 w Sat y a b 1 st w ω × a × b s 1 st v s 1 st t = 1 st u 𝑔 1 st v u Sat y a b 1 st t ω × a × b
127 85 126 syld w Sat y a b 1 st w ω × a × b v Sat y 1 st t = 1 st u 𝑔 1 st v u Sat y a b 1 st t ω × a × b
128 127 adantl y ω w Sat y a b 1 st w ω × a × b v Sat y 1 st t = 1 st u 𝑔 1 st v u Sat y a b 1 st t ω × a × b
129 128 com14 u Sat y v Sat y 1 st t = 1 st u 𝑔 1 st v y ω w Sat y a b 1 st w ω × a × b a b 1 st t ω × a × b
130 129 rexlimdv u Sat y v Sat y 1 st t = 1 st u 𝑔 1 st v y ω w Sat y a b 1 st w ω × a × b a b 1 st t ω × a × b
131 17 96 pm3.2i ω V s V
132 df-goal 𝑔 i 1 st u = 2 𝑜 i 1 st u
133 2onn 2 𝑜 ω
134 133 a1i 1 st u s i ω 2 𝑜 ω
135 opelxpi i ω 1 st u s i 1 st u ω × s
136 135 ancoms 1 st u s i ω i 1 st u ω × s
137 134 136 opelxpd 1 st u s i ω 2 𝑜 i 1 st u ω × ω × s
138 132 137 eqeltrid 1 st u s i ω 𝑔 i 1 st u ω × ω × s
139 138 3adant3 1 st u s i ω 1 st t = 𝑔 i 1 st u 𝑔 i 1 st u ω × ω × s
140 eleq1 1 st t = 𝑔 i 1 st u 1 st t ω × ω × s 𝑔 i 1 st u ω × ω × s
141 140 3ad2ant3 1 st u s i ω 1 st t = 𝑔 i 1 st u 1 st t ω × ω × s 𝑔 i 1 st u ω × ω × s
142 139 141 mpbird 1 st u s i ω 1 st t = 𝑔 i 1 st u 1 st t ω × ω × s
143 xpeq12 a = ω b = s a × b = ω × s
144 143 xpeq2d a = ω b = s ω × a × b = ω × ω × s
145 144 eleq2d a = ω b = s 1 st t ω × a × b 1 st t ω × ω × s
146 145 spc2egv ω V s V 1 st t ω × ω × s a b 1 st t ω × a × b
147 131 142 146 mpsyl 1 st u s i ω 1 st t = 𝑔 i 1 st u a b 1 st t ω × a × b
148 147 3exp 1 st u s i ω 1 st t = 𝑔 i 1 st u a b 1 st t ω × a × b
149 148 com23 1 st u s 1 st t = 𝑔 i 1 st u i ω a b 1 st t ω × a × b
150 149 a1d 1 st u s y ω 1 st t = 𝑔 i 1 st u i ω a b 1 st t ω × a × b
151 150 exlimiv s 1 st u s y ω 1 st t = 𝑔 i 1 st u i ω a b 1 st t ω × a × b
152 92 151 syl u Sat y w Sat y a b 1 st w ω × a × b y ω 1 st t = 𝑔 i 1 st u i ω a b 1 st t ω × a × b
153 152 ex u Sat y w Sat y a b 1 st w ω × a × b y ω 1 st t = 𝑔 i 1 st u i ω a b 1 st t ω × a × b
154 153 impcomd u Sat y y ω w Sat y a b 1 st w ω × a × b 1 st t = 𝑔 i 1 st u i ω a b 1 st t ω × a × b
155 154 com24 u Sat y i ω 1 st t = 𝑔 i 1 st u y ω w Sat y a b 1 st w ω × a × b a b 1 st t ω × a × b
156 155 rexlimdv u Sat y i ω 1 st t = 𝑔 i 1 st u y ω w Sat y a b 1 st w ω × a × b a b 1 st t ω × a × b
157 130 156 jaod u Sat y v Sat y 1 st t = 1 st u 𝑔 1 st v i ω 1 st t = 𝑔 i 1 st u y ω w Sat y a b 1 st w ω × a × b a b 1 st t ω × a × b
158 157 rexlimiv u Sat y v Sat y 1 st t = 1 st u 𝑔 1 st v i ω 1 st t = 𝑔 i 1 st u y ω w Sat y a b 1 st w ω × a × b a b 1 st t ω × a × b
159 158 adantl 2 nd t = u Sat y v Sat y 1 st t = 1 st u 𝑔 1 st v i ω 1 st t = 𝑔 i 1 st u y ω w Sat y a b 1 st w ω × a × b a b 1 st t ω × a × b
160 eqeq1 x = 1 st t x = 1 st u 𝑔 1 st v 1 st t = 1 st u 𝑔 1 st v
161 160 rexbidv x = 1 st t v Sat y x = 1 st u 𝑔 1 st v v Sat y 1 st t = 1 st u 𝑔 1 st v
162 eqeq1 x = 1 st t x = 𝑔 i 1 st u 1 st t = 𝑔 i 1 st u
163 162 rexbidv x = 1 st t i ω x = 𝑔 i 1 st u i ω 1 st t = 𝑔 i 1 st u
164 161 163 orbi12d x = 1 st t v Sat y x = 1 st u 𝑔 1 st v i ω x = 𝑔 i 1 st u v Sat y 1 st t = 1 st u 𝑔 1 st v i ω 1 st t = 𝑔 i 1 st u
165 164 rexbidv x = 1 st t u Sat y v Sat y x = 1 st u 𝑔 1 st v i ω x = 𝑔 i 1 st u u Sat y v Sat y 1 st t = 1 st u 𝑔 1 st v i ω 1 st t = 𝑔 i 1 st u
166 165 anbi2d x = 1 st t z = u Sat y v Sat y x = 1 st u 𝑔 1 st v i ω x = 𝑔 i 1 st u z = u Sat y v Sat y 1 st t = 1 st u 𝑔 1 st v i ω 1 st t = 𝑔 i 1 st u
167 eqeq1 z = 2 nd t z = 2 nd t =
168 167 anbi1d z = 2 nd t z = u Sat y v Sat y 1 st t = 1 st u 𝑔 1 st v i ω 1 st t = 𝑔 i 1 st u 2 nd t = u Sat y v Sat y 1 st t = 1 st u 𝑔 1 st v i ω 1 st t = 𝑔 i 1 st u
169 166 168 elopabi t x z | z = u Sat y v Sat y x = 1 st u 𝑔 1 st v i ω x = 𝑔 i 1 st u 2 nd t = u Sat y v Sat y 1 st t = 1 st u 𝑔 1 st v i ω 1 st t = 𝑔 i 1 st u
170 159 169 syl11 y ω w Sat y a b 1 st w ω × a × b t x z | z = u Sat y v Sat y x = 1 st u 𝑔 1 st v i ω x = 𝑔 i 1 st u a b 1 st t ω × a × b
171 77 170 jaod y ω w Sat y a b 1 st w ω × a × b t Sat y t x z | z = u Sat y v Sat y x = 1 st u 𝑔 1 st v i ω x = 𝑔 i 1 st u a b 1 st t ω × a × b
172 72 171 sylbid y ω w Sat y a b 1 st w ω × a × b t Sat suc y a b 1 st t ω × a × b
173 172 ex y ω w Sat y a b 1 st w ω × a × b t Sat suc y a b 1 st t ω × a × b
174 173 ralrimdv y ω w Sat y a b 1 st w ω × a × b t Sat suc y a b 1 st t ω × a × b
175 75 cbvralvw w Sat suc y a b 1 st w ω × a × b t Sat suc y a b 1 st t ω × a × b
176 174 175 syl6ibr y ω w Sat y a b 1 st w ω × a × b w Sat suc y a b 1 st w ω × a × b
177 2 4 6 8 37 176 finds N ω w Sat N a b 1 st w ω × a × b