Metamath Proof Explorer


Definition df-risefac

Description: Define the rising factorial function. This is the function ( A x. ( A + 1 ) x. ... ( A + N ) ) for complex A and nonnegative integers N . (Contributed by Scott Fenton, 5-Jan-2018)

Ref Expression
Assertion df-risefac RiseFac = x , n 0 k = 0 n 1 x + k

Detailed syntax breakdown

Step Hyp Ref Expression
0 crisefac class RiseFac
1 vx setvar x
2 cc class
3 vn setvar n
4 cn0 class 0
5 vk setvar k
6 cc0 class 0
7 cfz class
8 3 cv setvar n
9 cmin class
10 c1 class 1
11 8 10 9 co class n 1
12 6 11 7 co class 0 n 1
13 1 cv setvar x
14 caddc class +
15 5 cv setvar k
16 13 15 14 co class x + k
17 12 16 5 cprod class k = 0 n 1 x + k
18 1 3 2 4 17 cmpo class x , n 0 k = 0 n 1 x + k
19 0 18 wceq wff RiseFac = x , n 0 k = 0 n 1 x + k