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.

A181197 Number of 3 X n matrices containing a permutation of 1..3*n in increasing order rowwise, columnwise and (downwards) antidiagonally.

Table of values

n a(n)
1 1
2 1
3 4
4 29
5 290
6 3532
7 49100
8 750325
9 12310294
10 213446666
11 3868253164
12 72686739116
13 1407643591804
14 27964937748724
15 567853691242796
16 11751537336221989
17 247263499985110046
18 5279409371079693454
19 114199628255736623996
20 2499214354674134770354

List of values

[1, 1, 4, 29, 290, 3532, 49100, 750325, 12310294, 213446666, 3868253164, 72686739116, 1407643591804, 27964937748724, 567853691242796, 11751537336221989, 247263499985110046, 5279409371079693454, 114199628255736623996, 2499214354674134770354]

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

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