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A038074
Shifts left and changes sign under Weigh transform.
2
1, -1, 1, 0, -2, 2, 2, -6, 4, 8, -23, 12, 43, -95, 28, 223, -420, 6, 1194, -1860, -597, 6405, -8235, -6221, 34441, -35405, -48444, 184208, -143567, -337144, 976873, -512835, -2207538, 5112758, -1290534, -13896631, 26279179, 1478847, -84969584, 131756101
OFFSET
1,5
LINKS
N. J. A. Sloane, Transforms
MAPLE
b:= proc(n, i) option remember; `if`(n=0, 1, `if`(i<1, 0,
add(binomial(a(i$2), j)*b(n-i*j, i-1), j=0..n/i)))
end:
a:= n-> `if`(n=1, 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 == 1, 1, -b[n - 1, n - 1]];
Array[a, 60] (* Jean-François Alcover, Mar 01 2021, after Alois P. Heinz *)
CROSSREFS
Cf. A038073.
Sequence in context: A131904 A278264 A232114 * A059885 A259689 A300413
KEYWORD
sign,eigen
AUTHOR
Christian G. Bower, Jan 04 1999
STATUS
approved