A038072 Shifts left under Euler transform.

-1, -1, -1, 0, 1, 2, 0, -3, -5, -1, 11, 19, 4, -42, -78, -18, 172, 333, 88, -747, -1483, -436, 3355, 6834, 2193, -15417, -32248, -11206, 72264, 154900, 57929, -344282, -755103, -302126, 1661464, 3726663, 1586904, -8103245, -18581402, -8384292, 39876825

Offset

1,6

Links

Alois P. Heinz, Table of n, a(n) for n = 1..1000

N. J. A. Sloane, Transforms

Maple

with(numtheory): a:= proc(n) option remember; local d, j; if n=1 then -1 else (add(d*a(d), d=divisors(n-1)) +add(add(d*a(d), d=divisors(j)) *a(n-j), j=1..n-2))/(n-1) fi end: seq(a(n), n=1..40);  # Alois P. Heinz, Sep 06 2008

Mathematica

a[n_] := a[n] = If[n == 1, -1, (Sum[d a[d], {d, Divisors[n-1]}] + Sum[Sum[d a[d], {d, Divisors[j]}] a[n-j], {j, 1, n-2}])/(n-1)];
Array[a, 40] (* Jean-François Alcover, Nov 08 2020, after Alois P. Heinz *)

Crossrefs

Cf. A038073.

Sequence in context: A035347 A094126 A293269 * A215482 A161481 A272695

Adjacent sequences: A038069 A038070 A038071 * A038073 A038074 A038075

Keyword

sign,eigen

Author

Christian G. Bower, Jan 04 1999

Status

approved