A306188 Number of n-times strict partitions of n.

1, 1, 1, 4, 11, 41, 154, 904, 4927, 35398, 234454, 1965976, 16589885, 157974740, 1480736877, 16406078770, 177232251249, 2151696598160, 25726133391191, 346746928400037, 4607758596471426, 67562340652906942, 969200312705046531, 15386051753617360150

Offset

0,4

Links

Alois P. Heinz, Table of n, a(n) for n = 0..480

Maple

b:= proc(n, i, k) option remember; `if`(i*(i+1)/2<n, 0, `if`(n=0 or
      k=0, 1, b(n, i-1, k)+b(i$2, k-1)*b(n-i, min(n-i, i-1), k)))
    end:
a:= n-> b(n$3):
seq(a(n), n=0..25);

Mathematica

b[n_, i_, k_] := b[n, i, k] = If[i(i+1)/2 < n, 0, If[n == 0 || k == 0, 1, b[n, i - 1, k] + b[i, i, k - 1] b[n - i, Min[n - i, i - 1], k]]];
a[n_] := b[n, n, n];
a /@ Range[0, 25] (* Jean-François Alcover, Dec 08 2020, after Alois P. Heinz *)

Crossrefs

Cf. A000009, A261280, A306187.

Sequence in context: A151455 A149269 A149270 * A307702 A214167 A278988

Adjacent sequences: A306185 A306186 A306187 * A306189 A306190 A306191

Keyword

nonn

Author

Alois P. Heinz, Jan 27 2019

Status

approved