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.

A321511 Number of alternating sign n X n matrices excluding permutation matrices.

Table of values

n a(n)
0 0
1 0
2 0
3 1
4 18
5 309
6 6716
7 213308
8 10809896
9 911472580
10 129530643900
11 31095704935575
12 12611311380675900
13 8639383512070631700
14 9995541355360989190800
15 19529076234659969430529200
16 64427185703425668434106855840
17 358869201916137601091798728321296

List of values

[0, 0, 0, 1, 18, 309, 6716, 213308, 10809896, 911472580, 129530643900, 31095704935575, 12611311380675900, 8639383512070631700, 9995541355360989190800, 19529076234659969430529200, 64427185703425668434106855840, 358869201916137601091798728321296]

Started in 1964 by Neil J. A. Sloane | Maintained by The OEIS Foundation Inc.

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