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.

A220156 Number of 4Xn arrays of the minimum value of corresponding elements and their horizontal or diagonal neighbors in a random, but sorted with lexicographically nondecreasing rows and nonincreasing columns, 0..2 4Xn array.

Table of values

n a(n)
1 15
2 52
3 242
4 1174
5 4559
6 16110
7 53947
8 173732
9 539903
10 1620236
11 4698464
12 13180052
13 35802185
14 94277039
15 240952485
16 598495844
17 1446788180
18 3408685943
19 7838407335
20 17616947657
21 38749982170
22 83520468048
23 176604065342
24 366743870453

List of values

[15, 52, 242, 1174, 4559, 16110, 53947, 173732, 539903, 1620236, 4698464, 13180052, 35802185, 94277039, 240952485, 598495844, 1446788180, 3408685943, 7838407335, 17616947657, 38749982170, 83520468048, 176604065342, 366743870453]

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

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