cp's OEIS Frontend

This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

A296560 Number of normal semistandard Young tableaux whose shape is the conjugate of the integer partition with Heinz number n.

Original entry on oeis.org

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

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Author

Gus Wiseman, Feb 15 2018

Keywords

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).

Crossrefs

Programs

  • 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]