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.

A294491 Number of length 2n n-ary words that can be built by repeatedly inserting doublets into the initially empty word.

Table of values

n a(n)
0 1
1 1
2 6
3 87
4 2092
5 71445
6 3183156
7 175466347
8 11544312984
9 883404542025
10 77115832253380
11 7564442149980111
12 823833773843404776
13 98644885379708947357
14 12880909497761085034632
15 1821689155897508835803475
16 277402856595034529463789616
17 45253909471856604392088994065

List of values

[1, 1, 6, 87, 2092, 71445, 3183156, 175466347, 11544312984, 883404542025, 77115832253380, 7564442149980111, 823833773843404776, 98644885379708947357, 12880909497761085034632, 1821689155897508835803475, 277402856595034529463789616, 45253909471856604392088994065]

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

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