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.

A330644 Number of non-self-conjugate partitions of n.

Original entry on oeis.org

0, 0, 2, 2, 4, 6, 10, 14, 20, 28, 40, 54, 74, 98, 132, 172, 226, 292, 380, 484, 620, 784, 994, 1246, 1564, 1946, 2424, 2996, 3702, 4548, 5586, 6822, 8326, 10118, 12284, 14854, 17944, 21602, 25978, 31144, 37292, 44534, 53122, 63204, 75112, 89066, 105486, 124676, 147186, 173432
Offset: 0

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Author

Omar E. Pol, Jan 10 2020

Keywords

Comments

Also number of asymmetric Ferrers graphs with n nodes.

Examples

			For n = 5 the partitions of 5 and their respective Ferrers graphs are as follows:
.
  5 * * * * *    4 * * * *    3 * * *    3 * * *    2 * *    2 * *    1 *
                 1 *          2 * *      1 *        2 * *    1 *      1 *
                                         1 *        1 *      1 *      1 *
                                                             1 *      1 *
                                                                      1 *
The number 5 has seven partitions, and one of them [3, 1, 1] is a self-conjugate partition, hence the number of non-self-conjugate partitions of 5 is 7 - 1 = 6, so a(5) = 6.
On the other hand there are six asymmetric Ferrers graphs with n nodes, they are the graphs associated to the partitions [5], [4, 1], [3, 2], [2, 2, 1], [2, 1, 1, 1], [1, 1, 1, 1, 1], so a(5) = 6.
		

Crossrefs

Formula

a(n) = A000041(n) - A000700(n).
a(n) = 2*A000701(n).