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.

A268990 Number of n X 3 binary arrays with some element plus some horizontally or antidiagonally adjacent neighbor totalling two not more than once.

Table of values

n a(n)
1 7
2 35
3 174
4 849
5 4083
6 19416
7 91491
8 427863
9 1988142
10 9187653
11 42256599
12 193542240
13 883204143
14 4017241083
15 18219040206
16 82410172617
17 371879874987
18 1674499435176
19 7525052043819
20 33755742643791
21 151168877259918
22 675941817039645

List of values

[7, 35, 174, 849, 4083, 19416, 91491, 427863, 1988142, 9187653, 42256599, 193542240, 883204143, 4017241083, 18219040206, 82410172617, 371879874987, 1674499435176, 7525052043819, 33755742643791, 151168877259918, 675941817039645]

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

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