A229279 Number of ascending runs in {1,...,5}^n.
0, 5, 40, 275, 1750, 10625, 62500, 359375, 2031250, 11328125, 62500000, 341796875, 1855468750, 10009765625, 53710937500, 286865234375, 1525878906250, 8087158203125, 42724609375000, 225067138671875, 1182556152343750, 6198883056640625, 32424926757812500
Offset: 0
Links
- Alois P. Heinz, Table of n, a(n) for n = 0..1000
- Index entries for linear recurrences with constant coefficients, signature (10,-25).
Crossrefs
Column k=5 of A229079.
Programs
-
Maple
a:= n-> `if`(n=0, 0, 5^(n-1)*(3*n+2)): seq(a(n), n=0..30);
Formula
G.f.: -5*(2*x-1)*x/(5*x-1)^2.
a(n) = 5^(n-1)*(3*n+2) for n>0, a(0) = 0.