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A320737
Number of partitions of n with six sorts of part 1 which are introduced in ascending order.
4
1, 1, 3, 7, 20, 63, 233, 965, 4425, 21904, 114910, 628754, 3544272, 20393306, 118986963, 700768255, 4152987416, 24714368292, 147480695339, 881688073414, 5277421580515, 31613933962624, 189481916086717, 1136086826214117, 6813308511956936, 40867019987219945
OFFSET
0,3
LINKS
MAPLE
b:= proc(n, i) option remember; `if`(n=0 or i<2, add(
Stirling2(n, j), j=0..6), add(b(n-i*j, i-1), j=0..n/i))
end:
a:= n-> b(n$2):
seq(a(n), n=0..40);
MATHEMATICA
b[n_, i_] := b[n, i] = If[n == 0 || i < 2, Sum[StirlingS2[n, j], {j, 0, 6}], Sum[b[n - i j, i - 1], {j, 0, n/i}]];
a[n_] := b[n, n];
a /@ Range[0, 40] (* Jean-François Alcover, Dec 07 2020, after Alois P. Heinz *)
CROSSREFS
Column k=6 of A292745.
Sequence in context: A320735 A176697 A320736 * A320738 A320739 A320740
KEYWORD
nonn
AUTHOR
Alois P. Heinz, Oct 20 2018
STATUS
approved