Metamath Proof Explorer


Theorem zplusmodne

Description: A nonnegative integer is not itself plus a positive integer modulo an integer greater than 1 and the positive integer. (Contributed by AV, 6-Sep-2025)

Ref Expression
Assertion zplusmodne N 2 A K 1 ..^ N A + K mod N A mod N

Proof

Step Hyp Ref Expression
1 eluz2nn N 2 N
2 1 3ad2ant1 N 2 A K 1 ..^ N N
3 simp2 N 2 A K 1 ..^ N A
4 elfzoelz K 1 ..^ N K
5 4 3ad2ant3 N 2 A K 1 ..^ N K
6 3 5 zaddcld N 2 A K 1 ..^ N A + K
7 3 zcnd N 2 A K 1 ..^ N A
8 4 zcnd K 1 ..^ N K
9 8 3ad2ant3 N 2 A K 1 ..^ N K
10 7 9 pncan2d N 2 A K 1 ..^ N A + K - A = K
11 elfzo1 K 1 ..^ N K N K < N
12 nnge1 K 1 K
13 12 anim1i K K < N 1 K K < N
14 13 3adant2 K N K < N 1 K K < N
15 11 14 sylbi K 1 ..^ N 1 K K < N
16 15 3ad2ant3 N 2 A K 1 ..^ N 1 K K < N
17 16 adantr N 2 A K 1 ..^ N A + K - A = K 1 K K < N
18 breq2 A + K - A = K 1 A + K - A 1 K
19 18 adantl N 2 A K 1 ..^ N A + K - A = K 1 A + K - A 1 K
20 breq1 A + K - A = K A + K - A < N K < N
21 20 adantl N 2 A K 1 ..^ N A + K - A = K A + K - A < N K < N
22 19 21 anbi12d N 2 A K 1 ..^ N A + K - A = K 1 A + K - A A + K - A < N 1 K K < N
23 17 22 mpbird N 2 A K 1 ..^ N A + K - A = K 1 A + K - A A + K - A < N
24 10 23 mpdan N 2 A K 1 ..^ N 1 A + K - A A + K - A < N
25 difltmodne N A + K A 1 A + K - A A + K - A < N A + K mod N A mod N
26 2 6 3 24 25 syl121anc N 2 A K 1 ..^ N A + K mod N A mod N