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A296188
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Number of normal semistandard Young tableaux whose shape is the integer partition with Heinz number n.
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49
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1, 1, 2, 1, 4, 4, 8, 1, 6, 12, 16, 6, 32, 32, 28, 1, 64, 16, 128, 24, 96, 80, 256, 8, 44, 192, 22, 80, 512, 96, 1024, 1, 288, 448, 224, 30, 2048, 1024, 800, 40, 4096, 400, 8192, 240, 168, 2304, 16384, 10, 360, 204, 2112, 672, 32768, 68, 832, 160, 5376, 5120
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OFFSET
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1,3
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COMMENTS
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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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REFERENCES
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Richard P. Stanley, Enumerative Combinatorics Volume 2, Cambridge University Press, 1999, Chapter 7.10.
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LINKS
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FORMULA
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Let b(n) = Sum_{d|n, d>1} b(n * d' / d) where if d = Product_i prime(s_i)^m(i) then d' = Product_i prime(s_i - 1)^m(i) and prime(0) = 1. Then a(n) = b(conj(n)) where conj = A122111.
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EXAMPLE
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The a(9) = 6 tableaux:
1 3 1 2 1 2 1 2 1 1 1 1
2 4 3 4 3 3 2 3 2 3 2 2
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MATHEMATICA
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conj[y_List]:=If[Length[y]===0, y, Table[Length[Select[y, #>=k&]], {k, 1, Max[y]}]];
conj[n_Integer]:=Times@@Prime/@conj[If[n===1, {}, Join@@Cases[FactorInteger[n]//Reverse, {p_, k_}:>Table[PrimePi[p], {k}]]]];
ssyt[n_]:=If[n===1, 1, Sum[ssyt[n/q*Times@@Cases[FactorInteger[q], {p_, k_}:>If[p===2, 1, NextPrime[p, -1]^k]]], {q, Rest[Divisors[n]]}]];
Table[ssyt[conj[n]], {n, 50}]
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CROSSREFS
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Cf. A000085, A001222, A056239, A063834, A112798, A122111, A138178, A153452, A191714, A210391, A228125, A296150, A296560, A296561, A299202, A299966, A300056, A300121.
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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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