A144821 Shifts left when Dirichlet convolution with a (DC:(b,a)->c) applied 8 times.
1, 1, 9, 81, 765, 6885, 62613, 563517, 5077569, 45701037, 411364413, 3702279717, 33321067929, 299889611361, 2699011010385, 24291099589185, 218619937132623, 1967579434193607, 17708215277809323, 159373937500283907
Offset: 1
Links
- Alois P. Heinz, Table of n, a(n) for n = 1..1000
- N. J. A. Sloane, Transforms
Crossrefs
8th column of A144823.
Programs
-
Maple
with(numtheory): dc:= proc(b,c) proc(n) option remember; add(b(d) *c(n/d), d=`if`(n<0,{},divisors(n))) end end: A:= proc(n, k) local a, b, t; b[1]:= dc(a,a); for t from 2 to k do b[t]:= dc(b[t-1],a) od: a:= n-> `if`(n=1, 1, b[k](n-1)); a(n) end: a:= n-> A(n,8): seq(a(n), n=1..30);