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A246234
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Number of compositions of n into exactly seven different parts with distinct multiplicities.
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2
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2431106898187968000, 25830510793247160000, 121150160426367072000, 478913588068635720000, 1848522650426852400000, 6067325851827648408000, 19158973516499432616000, 59882095876893754464000, 173801554657753702680000, 487295849448575903736000
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OFFSET
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84,1
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LINKS
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MATHEMATICA
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$RecursionLimit = 1000; 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, 7]; Table[a[n], {n, 84, 100}] (* Jean-François Alcover, Feb 11 2015, after Alois P. Heinz *)
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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STATUS
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approved
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