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.

A135457 a(n) = (2n-1)!! * Sum_{k=0..n-2}(-1)^k/(2k+1).

Table of values

n a(n)
1 0
2 3
3 10
4 91
5 684
6 8679
7 100542
8 1664055
9 25991640
10 532354635
11 10455799410
12 255542155155
13 6044821114500
14 171748491958575
15 4751436512960550
16 153911731348760175
17 4874807783839316400
18 177334729873063945875

List of values

[0, 3, 10, 91, 684, 8679, 100542, 1664055, 25991640, 532354635, 10455799410, 255542155155, 6044821114500, 171748491958575, 4751436512960550, 153911731348760175, 4874807783839316400, 177334729873063945875]

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

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