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.

A219473 Number of 3Xn arrays of the minimum value of corresponding elements and their horizontal or antidiagonal neighbors in a random, but sorted with lexicographically nondecreasing rows and columns, 0..3 3Xn array.

Table of values

n a(n)
1 20
2 82
3 673
4 4838
5 28159
6 143718
7 674954
8 2941342
9 11981143
10 45898940
11 166443227
12 574474013
13 1895549798
14 6001932167
15 18298398284
16 53884690148
17 153709998598
18 425853237243
19 1148567805278
20 3022012284611
21 7771027231688
22 19561835095982

List of values

[20, 82, 673, 4838, 28159, 143718, 674954, 2941342, 11981143, 45898940, 166443227, 574474013, 1895549798, 6001932167, 18298398284, 53884690148, 153709998598, 425853237243, 1148567805278, 3022012284611, 7771027231688, 19561835095982]

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

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