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A292884
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Number of ways to shuffle together a multiset of compositions to form a composition of n.
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25
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1, 3, 8, 25, 76, 248, 806, 2714, 9205, 31846, 111185, 393224
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OFFSET
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1,2
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LINKS
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EXAMPLE
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The a(3)=8 shuffles are:
(111)<=((111)), (111)<=((1)(11)), (111)<=((1)(1)(1)),
(12)<=((12)), (12)<=((1)(2)),
(21)<=((21)), (21)<=((1)(2)),
(3)<=((3)).
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MATHEMATICA
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nn=10;
comps[0]:={{}}; comps[n_]:=Join@@Table[Prepend[#, i]&/@comps[n-i], {i, n}];
sps[{}]:={{}}; sps[set:{i_, ___}]:=Join@@Function[s, Prepend[#, s]&/@sps[Complement[set, s]]]/@Cases[Subsets[set], {i, ___}];
dealings[q_]:=Union[Function[ptn, Sort[q[[#]]&/@ptn]]/@sps[Range[Length[q]]]];
Table[Total[Length/@dealings/@comps[n]], {n, nn}]
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CROSSREFS
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KEYWORD
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nonn,more
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AUTHOR
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EXTENSIONS
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STATUS
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approved
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