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.

A220637 Number of ways to reciprocally link elements of an 7Xn array either to themselves or to exactly two horizontal or antidiagonal neighbors.

Table of values

n a(n)
1 1
2 1
3 21
4 1081
5 49448
6 1932695
7 72097810
8 2685329069
9 100377946990
10 3759405889469
11 140807441642550
12 5273589943694582
13 197503772671988555
14 7396752550237211667
15 277016765034509275485
16 10374589395033217351070

List of values

[1, 1, 21, 1081, 49448, 1932695, 72097810, 2685329069, 100377946990, 3759405889469, 140807441642550, 5273589943694582, 197503772671988555, 7396752550237211667, 277016765034509275485, 10374589395033217351070]

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

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