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.

A012821 Expansion of e.g.f. exp(sec(x)*arcsinh(x)).

Table of values

n a(n)
0 1
1 1
2 1
3 3
4 9
5 45
6 225
7 1071
8 6993
9 56697
10 467745
11 3279419
12 29529753
13 376156261
14 4297350785
15 35274762407
16 378759492257
17 8003761282417
18 122599030798017
19 853554115621363
20 8002975063348265
21 450081179390735645

List of values

[1, 1, 1, 3, 9, 45, 225, 1071, 6993, 56697, 467745, 3279419, 29529753, 376156261, 4297350785, 35274762407, 378759492257, 8003761282417, 122599030798017, 853554115621363, 8002975063348265, 450081179390735645]

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

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