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A246230 Number of compositions of n into exactly three different parts with distinct multiplicities. 2
60, 285, 498, 1438, 2816, 5208, 11195, 24094, 38523, 85182, 148051, 255922, 512428, 991423, 1573152, 3318750, 5820718, 9712145, 19523028, 36637218, 58805129, 121712569, 216006156, 360123456, 720094287, 1340734558, 2184432420, 4453145090, 7987036106, 13417450294 (list; graph; refs; listen; history; text; internal format)
OFFSET

10,1

LINKS

Alois P. Heinz and Vaclav Kotesovec, Table of n, a(n) for n = 10..220 (first 120 terms from Alois P. Heinz)

MATHEMATICA

b[n_, i_, s_List] := b[n, i, s] = If[n == 0, Total[s]!, If[i<1, 0, Expand[ Sum[ If[j>0 && MemberQ[s, j], 0, If[j == 0, 1, x]*b[n-i*j, i-1, If[j == 0, s, s ~Union~{j}]]/j!], {j, 0, n/i}]]]]; a[n_] := Coefficient[b[n, n, {}], x, 3]; Table[a[n], {n, 10, 40}] (* Jean-Fran├žois Alcover, Feb 11 2015, after Alois P. Heinz *)

CROSSREFS

Column k=3 of A242896.

Sequence in context: A328156 A160917 A100154 * A100148 A100151 A179811

Adjacent sequences:  A246227 A246228 A246229 * A246231 A246232 A246233

KEYWORD

nonn

AUTHOR

Alois P. Heinz, Aug 19 2014

STATUS

approved

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Last modified August 9 05:12 EDT 2020. Contains 336319 sequences. (Running on oeis4.)