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.

A132993 Triangle t(n,m) = P(n-m+1) * P(m+1) read by rows, 0<=m<=n, where P=A000041 are the partition numbers.

Original entry on oeis.org

1, 2, 2, 3, 4, 3, 5, 6, 6, 5, 7, 10, 9, 10, 7, 11, 14, 15, 15, 14, 11, 15, 22, 21, 25, 21, 22, 15, 22, 30, 33, 35, 35, 33, 30, 22, 30, 44, 45, 55, 49, 55, 45, 44, 30, 42, 60, 66, 75, 77, 77, 75, 66, 60, 42, 56, 84, 90, 110, 105, 121, 105, 110, 90, 84, 56
Offset: 0

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Author

Roger L. Bagula and Gary W. Adamson, Aug 27 2008

Keywords

Examples

			1;
2, 2;
3, 4, 3;
5, 6, 6, 5;
7, 10, 9, 10, 7;
11, 14, 15, 15, 14, 11;
15, 22, 21, 25, 21, 22, 15;
22, 30, 33, 35, 35, 33, 30, 22;
30, 44, 45, 55, 49, 55, 45, 44, 30;
42, 60, 66, 75, 77, 77, 75, 66, 60, 42;
56, 84, 90, 110, 105, 121, 105, 110, 90, 84, 56;
		

Crossrefs

Cf. A000041, A048574 (row sums).

Programs

  • Maple
    A132993 := proc(n,m)
            combinat[numbpart](n-m+1)*combinat[numbpart](m+1) ;
    end proc:
    seq(seq(A132993(n,k),k=0..n),n=0..12) ; # R. J. Mathar, Nov 11 2011
  • Mathematica
    << DiscreteMath`Combinatorica`; << DiscreteMath`IntegerPartitions`; Clear[t, n, m]; t[n_, m_] = PartitionsP[n - m + 1]*PartitionsP[m + 1]; Table[Table[t[n, m], {m, 0, n}], {n, 0, 10}]; Flatten[%]