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.

A134133 A certain partition array in Abramowitz-Stegun order (A-St order).

Original entry on oeis.org

1, 2, 1, 6, 2, 1, 24, 6, 4, 2, 1, 120, 24, 12, 6, 4, 2, 1, 720, 120, 48, 36, 24, 12, 8, 6, 4, 2, 1, 5040, 720, 240, 144, 120, 48, 36, 24, 24, 12, 8, 6, 4, 2, 1, 40320, 5040, 1440, 720, 576, 720, 240, 144, 96, 72, 120, 48, 36, 24, 16, 24, 12, 8, 6, 4, 2, 1, 362880, 40320, 10080
Offset: 1

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Author

Wolfdieter Lang, Oct 12 2007

Keywords

Comments

The sequence of row lengths is A000041 (partition numbers) [1, 2, 3, 5, 7, 11, 15, 22, 30, 42,...].
Partition number array M_3(2)= A130561 divided by partition number array M_3 = M_3(1) = A036040.

Examples

			[1], [2,1], [6,2,1], [24,6,4,2,1], [120,24,12,6,4,2,1], ...
		

Crossrefs

With another ordering of the partitions this becomes A069123.
Cf. A134134 (triangle obtained by summing same m numbers).

Formula

a(n,k) = A130561(n,k)/A036040(n,k) (division of partition arrays M_3(2) by M_3).
a(n,k) = product(j!^e(n,k,j),j=1..n) with the exponent e(n,k,j) of j in the k-th partition of n in the A-St ordering of the partitions of n.