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A303586
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Number of partitions of [n] that contain no isolated singletons.
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4
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1, 0, 1, 1, 2, 3, 6, 11, 23, 47, 103, 226, 518, 1200, 2867, 6946, 17234, 43393, 111419, 290242, 768901, 2065172, 5630083, 15549403, 43527487, 123343911, 353864422, 1026935904, 3014535166, 8945274505, 26829206798, 81293234754, 248805520401, 768882019073, 2398686176048, 7552071250781
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OFFSET
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0,5
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COMMENTS
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LINKS
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MAPLE
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f:=proc(n) local j;
add(combinat:-bell(j-1)*binomial(n-j-1, j-1), j=0..floor(n/2));
end;
[seq(f(n), n=0..100)];
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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EXTENSIONS
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STATUS
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approved
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