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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.

A119880 Expansion of e.g.f. exp(2x)*sech(x).

Table of values

n a(n)
0 1
1 2
2 3
3 2
4 -3
5 2
6 63
7 2
8 -1383
9 2
10 50523
11 2
12 -2702763
13 2
14 199360983
15 2
16 -19391512143
17 2
18 2404879675443
19 2
20 -370371188237523
21 2
22 69348874393137903
23 2
24 -15514534163557086903
25 2
26 4087072509293123892363
27 2
28 -1252259641403629865468283
29 2
30 441543893249023104553682823

List of values

[1, 2, 3, 2, -3, 2, 63, 2, -1383, 2, 50523, 2, -2702763, 2, 199360983, 2, -19391512143, 2, 2404879675443, 2, -370371188237523, 2, 69348874393137903, 2, -15514534163557086903, 2, 4087072509293123892363, 2, -1252259641403629865468283, 2, 441543893249023104553682823]

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

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