A144318 Shifts left when Dirichlet convolution (DC:(b,b)->a) applied 4 times.

1, 1, 16, 256, 4216, 67456, 1083136, 17330176, 277344816, 4437547776, 71001776256, 1136028420096, 18176471920896, 290823550734336, 4653177071702016, 74450833163421696, 1191213334782285596, 19059413356516569536, 304950613771087329536, 4879209820337397272576

Offset

1,3

Links

Alois P. Heinz, Table of n, a(n) for n = 1..500

N. J. A. Sloane, Transforms

Maple

k:=4: 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:='a': b[1]:= dc(a, a): for t from 2 to k do b[t]:= dc(b[t-1], b[t-1]) od: a:= n-> `if`(n=1, 1, b[k](n-1)): seq (a(n), n=1..30);

Crossrefs

4th column of A144324.

Sequence in context: A229101 A220175 A001025 * A230142 A247165 A204080

Adjacent sequences: A144315 A144316 A144317 * A144319 A144320 A144321

Keyword

eigen,nonn

Author

Alois P. Heinz, Sep 17 2008

Status

approved