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.

A219878 Number of nX3 arrays of the minimum value of corresponding elements and their horizontal, diagonal or antidiagonal neighbors in a random, but sorted with lexicographically nondecreasing rows and nonincreasing columns, 0..2 nX3 array.

Table of values

n a(n)
1 6
2 11
3 47
4 146
5 410
6 1069
7 2701
8 6645
9 15787
10 36047
11 79071
12 166909
13 339837
14 668982
15 1276058
16 2363344
17 4258060
18 7476554
19 12815234
20 21476998
21 35244068
22 56710659
23 89591851
24 139128423
25 212611297
26 320053673
27 475043961
28 695818283
29 1006597679

List of values

[6, 11, 47, 146, 410, 1069, 2701, 6645, 15787, 36047, 79071, 166909, 339837, 668982, 1276058, 2363344, 4258060, 7476554, 12815234, 21476998, 35244068, 56710659, 89591851, 139128423, 212611297, 320053673, 475043961, 695818283, 1006597679]

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

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