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A296560
Number of normal semistandard Young tableaux whose shape is the conjugate of the integer partition with Heinz number n.
2
1, 1, 1, 2, 1, 4, 1, 4, 6, 6, 1, 12, 1, 8, 16, 8, 1, 28, 1, 24, 30, 10, 1, 32, 22, 12, 44, 40, 1, 96, 1, 16, 48, 14, 68, 96, 1, 16, 70, 80, 1, 220, 1, 60, 204, 18, 1, 80, 90, 168, 96, 84, 1, 224, 146, 160, 126, 20, 1, 400, 1, 22, 584, 32, 264, 416, 1, 112, 160
OFFSET
1,4
COMMENTS
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).
MATHEMATICA
a[n_]:=If[n===1, 1, Sum[a[n/q*Times@@Cases[FactorInteger[q], {p_, k_}:>If[p===2, 1, NextPrime[p, -1]^k]]], {q, Rest[Divisors[n]]}]];
Array[a, 100]
KEYWORD
nonn
AUTHOR
Gus Wiseman, Feb 15 2018
STATUS
approved