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.

A209080 Number of chess diagrams that can be obtained in exactly one way in n plies and cannot be obtained in fewer plies. This is also the number of dual-free shortest proof games in n plies.

Table of values

n a(n)
0 1
1 20
2 400
3 1702
4 8659
5 49401
6 287740
7 1934794
8 11569093
9 65443733
10 360231372
11 1872156836

List of values

[1, 20, 400, 1702, 8659, 49401, 287740, 1934794, 11569093, 65443733, 360231372, 1872156836]

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

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