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.

A134285 Triangle of numbers obtained from the partition array A134284.

Original entry on oeis.org

1, 3, 1, 10, 3, 1, 35, 19, 3, 1, 126, 65, 19, 3, 1, 462, 331, 92, 19, 3, 1, 1716, 1190, 421, 92, 19, 3, 1, 6435, 5587, 1805, 502, 92, 19, 3, 1, 24310, 20613, 8771, 2075, 502, 92, 19, 3, 1, 92378, 92821, 35726, 10616, 2318, 502, 92, 19, 3, 1, 352716, 347930, 160205
Offset: 1

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Author

Wolfdieter Lang, Nov 13 2007

Keywords

Comments

This triangle is called s2(3)'.

Examples

			Triangle starts:
1
3, 1
10, 3, 1
35, 19, 3, 1
126, 65, 19, 3, 1
...
a(4,2)=19 because the m=2 parts partitions (1^1,3^1) and (2^2) of n=4 lead to 1^1*10^1 + 3^2 =19, since A001700(n-1)=[1,3,10,...], n>=1.
		

Crossrefs

Row sums A134826. Alternating row sums A134827.
Cf. A001700.

Formula

a(n,m) = sum(product(s2(3;j,1)^e(n,m,q,j),j=1..n),k=1..p(n,m)) if n>=m>=1, else 0. Here p(n,m)=A008284(n,m), the number of m parts partitions of n and e(n,m,q,j) is the exponent of j in the q-th m part partition of n. s2(3;n,1) = A035324(n,1) = A001700(n-1) = binomial(2*n-1,n).
Row sums = A001700. Triangle A134285 = A001263 * A000012. - Gary W. Adamson, Nov 19 2007