A144820 Shifts left when Dirichlet convolution with a (DC:(b,a)->c) applied 6 times.

1, 1, 7, 49, 364, 2548, 18130, 126910, 890463, 6234270, 43655178, 305586246, 2139225879, 14974581153, 104822829531, 733759913733, 5136324781952, 35954273473664, 251679952469351, 1761759667285457, 12332317933624871

Offset: 1

Author

Alois P. Heinz, Sep 21 2008

Keywords

• eigen
• nonn

Links

• Alois P. Heinz, Table of n, a(n) for n = 1..500
• N. J. A. Sloane, Transforms

Crossrefs

6th 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,6): seq(a(n), n=1..30);