A144373 Shifts 9 places left under Dirichlet convolution.
1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 2, 2, 3, 2, 4, 2, 4, 3, 4, 4, 8, 6, 6, 10, 7, 8, 10, 8, 12, 18, 16, 12, 28, 15, 22, 22, 22, 24, 48, 32, 30, 60, 38, 46, 57, 44, 56, 102, 76, 60, 142, 76, 108, 124, 100, 112, 234, 153, 136, 292, 174, 216, 276, 204, 246, 476, 330, 272, 642, 348, 464
Offset: 1
Links
- Alois P. Heinz, Table of n, a(n) for n = 1..1000
- N. J. A. Sloane, Transforms
Programs
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Maple
k:= 9: with(numtheory): dck:= proc(b,c) proc(n, k) option remember; add(b(d,k) *c(n/d,k), d=`if`(n<0,{}, divisors(n))) end end: B:= dck(T,T): T:= (n, k)-> if n<=k then 1 else B(n-k, k) fi: a:= n-> T(n,k): seq(a(n), n=1..80);
Formula
G.f.: x + x^2 + x^3 + x^4 + x^5 + x^6 + x^7 + x^8 + x^9 * (1 + Sum_{i>=1} Sum_{j>=1} a(i)*a(j)*x^(i*j)). - Ilya Gutkovskiy, May 09 2019