A038073 Shifts left under Weigh transform.

-1, -1, 0, 0, 1, 0, -1, -1, 1, 2, 0, -3, -3, 2, 8, 4, -10, -18, 1, 36, 33, -36, -102, -33, 170, 238, -95, -578, -401, 762, 1599, 97, -3184, -3493, 2950, 10277, 4570, -16611, -26794, 6751, 63040, 51658, -78369, -190465, -34209, 365790, 455401, -296331, -1275020

Offset

1,10

Links

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

N. J. A. Sloane, Transforms

Maple

b:= proc(n, i) option remember; `if`(n=0, 1, `if`(i<1, 0,
      add(binomial(a(i), j)*b(n-i*j, i-1), j=0..n/i)))
    end:
a:= n-> `if`(n<2, -1, b((n-1)$2)):
seq(a(n), n=1..60); # Alois P. Heinz, May 20 2013

Mathematica

b[n_, i_] := b[n, i] = If[n==0, 1, If[i<1, 0, Sum[Binomial[a[i], j]*b[n-i*j, i-1], {j, 0, n/i}]]]; a[n_] := If[n<2, -1, b[n-1, n-1]]; Table[a[n], {n, 1, 60}] (* Jean-François Alcover, Feb 27 2017, after Alois P. Heinz *)

Crossrefs

Cf. A038072, A038074.

Sequence in context: A105569 A068455 A329098 * A283981 A291307 A239313

Adjacent sequences: A038070 A038071 A038072 * A038074 A038075 A038076

Keyword

sign,eigen

Author

Christian G. Bower, Jan 04 1999

Status

approved