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.

A322487 Number of (3*n) X n matrices with nonnegative integer entries and each column sum being 3 up to permutation of rows.

Table of values

n a(n)
0 1
1 3
2 31
3 686
4 27036
5 1688360
6 154703688
7 19692332568
8 3342458334775
9 732812082630803
10 202322386045180686
11 68898094282978653925
12 28443422251718020038049
13 14029033632468285836567998
14 8164217197799501761637725983
15 5545466507405459243366712102466

List of values

[1, 3, 31, 686, 27036, 1688360, 154703688, 19692332568, 3342458334775, 732812082630803, 202322386045180686, 68898094282978653925, 28443422251718020038049, 14029033632468285836567998, 8164217197799501761637725983, 5545466507405459243366712102466]

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

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