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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.

A296939 Expansion of e.g.f. sec(x*tan(x/2)) (even powers only).

Table of values

n a(n)
0 1
1 0
2 3
3 15
4 644
5 17145
6 1124673
7 74115496
8 7730031915
9 921044459943
10 145334164141820
11 26830525240048761
12 6053646614467427553
13 1586816790903080698000
14 487642998132913180824819
15 171640559783810345998524735
16 69078935661419038650738789428

List of values

[1, 0, 3, 15, 644, 17145, 1124673, 74115496, 7730031915, 921044459943, 145334164141820, 26830525240048761, 6053646614467427553, 1586816790903080698000, 487642998132913180824819, 171640559783810345998524735, 69078935661419038650738789428]

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

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