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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.

A116857 Triangle read by rows: T(n,k) is the number of partitions of n into distinct odd parts, the largest of which is k (n>=1, k>=1).

Original entry on oeis.org

1, 0, 0, 0, 1, 0, 0, 1, 0, 0, 0, 0, 1, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 1, 0, 1, 0, 0, 0, 0, 1, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 1, 0, 1, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 1, 0, 1, 0, 1, 0, 0, 0, 0, 0, 0, 1, 0, 1, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 1, 0, 1, 0, 0, 0, 0, 0, 0, 1, 0, 1, 0, 1, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 2, 0, 1, 0, 1, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 2, 0, 1, 0, 1, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 2, 0, 1, 0, 1, 0, 1, 0, 1
Offset: 1

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Author

Emeric Deutsch, Feb 24 2006

Keywords

Comments

Both rows 2n-1 and 2n have 2n-1 terms each. Row sums yield A000700. T(n,2k)=0 Sum(k*T(n,k),k>=1) = A092316(n).

Examples

			T(20,11)=2 because we have [11,9] and [11,5,3,1].
T(30,17)=3 because we have [17,13],[17,9,3,1] and [17,7,5,1].
Triangle starts:
  1;
  0;
  0,0,1;
  0,0,1;
  0,0,0,0,1;
  0,0,0,0,1;
  0,0,0,0,0,0,1;
  0,0,0,0,1,0,1;
  ...
		

Crossrefs

Programs

  • Maple
    g:=sum(t^(2*j-1)*x^(2*j-1)*product(1+x^(2*i-1),i=1..j-1),j=1..30): gser:=simplify(series(g,x=0,22)): for n from 1 to 20 do P[n]:=sort(coeff(gser,x^n)) od: for n from 1 to 20 do seq(coeff(P[n],t^j),j=1..2*ceil(n/2)-1) od; # yields sequence in triangular form

Formula

G.f.: sum(t^(2j-1)*x^(2j-1)*product(1+x^(2i-1), i=1..j-1), j=1..infinity).