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A300121
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Number of normal generalized Young tableaux, of shape the integer partition with Heinz number n, with all rows and columns weakly increasing and all regions connected skew partitions.
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38
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1, 1, 2, 2, 4, 5, 8, 4, 11, 12, 16, 12, 32, 28, 31, 8, 64, 31, 128, 33, 82, 64, 256, 28, 69, 144, 69, 86, 512, 105, 1024, 16, 208, 320, 209, 82, 2048, 704, 512, 86, 4096, 318, 8192, 216, 262, 1536, 16384, 64, 465, 262, 1232, 528, 32768, 209, 588, 245, 2912, 3328
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OFFSET
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1,3
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COMMENTS
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The diagram of a connected skew partition is required to be connected as a polyomino but can have empty rows or columns. A generalized Young tableau of shape y is an array obtained by replacing the dots in the Ferrers diagram of y with positive integers. A tableau is normal if its entries span an initial interval of positive integers. The Heinz number of an integer partition (y_1,...,y_k) is prime(y_1)*...*prime(y_k).
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LINKS
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Table of n, a(n) for n=1..58.
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EXAMPLE
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The a(9) = 11 tableaux:
1 1
1 1
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2 1 1 1 1 1 1 2
1 1 1 2 2 2 1 2
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1 1 1 2 1 2 1 3
2 3 1 3 3 3 2 3
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1 2 1 3
3 4 2 4
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MATHEMATICA
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undcon[y_]:=Select[Tuples[Range[0, #]&/@y], Function[v, GreaterEqual@@v&&With[{r=Select[Range[Length[y]], y[[#]]=!=v[[#]]&]}, Or[Length[r]<=1, And@@Table[v[[i]]<y[[i+1]], {i, Range[Min@@r, Max@@r-1]}]]]]];
cos[y_]:=cos[y]=With[{sam=Most[undcon[y]]}, If[Length[sam]===0, If[Total[y]===0, {{}}, {}], Join@@Table[Prepend[#, y]&/@cos[sam[[k]]], {k, 1, Length[sam]}]]];
primeMS[n_]:=If[n===1, {}, Flatten[Cases[FactorInteger[n], {p_, k_}:>Table[PrimePi[p], {k}]]]];
Table[Length[cos[Reverse[primeMS[n]]]], {n, 50}]
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CROSSREFS
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Cf. A000085, A000898, A056239, A006958, A138178, A153452, A238690, A259479, A259480, A296150, A296561, A297388, A299699, A299925, A299926, A300056, A300060, A300118, A300120, A300122, A300123, A300124.
Sequence in context: A319160 A292382 A296561 * A267046 A308902 A166515
Adjacent sequences: A300118 A300119 A300120 * A300122 A300123 A300124
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KEYWORD
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nonn
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AUTHOR
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Gus Wiseman, Feb 25 2018
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STATUS
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approved
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