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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.

A009403 Expansion of e.g.f. log(1 + tanh(x)^2), even powers only.

Table of values

n a(n)
0 0
1 2
2 -28
3 992
4 -69088
5 8110592
6 -1448424448
7 366436769792
8 -124760831684608
9 55014520738414592
10 -30501848618302701568
11 20768078187214502100992
12 -17035983844637174375907328
13 16570619538920401323784404992

List of values

[0, 2, -28, 992, -69088, 8110592, -1448424448, 366436769792, -124760831684608, 55014520738414592, -30501848618302701568, 20768078187214502100992, -17035983844637174375907328, 16570619538920401323784404992]

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

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