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.

A352149 a(n) = Sum_{k=0..n-1} binomial(n,k)^2 * (n-k-1)!.

Table of values

n a(n)
0 0
1 1
2 5
3 20
4 90
5 499
6 3395
7 27474
8 256984
9 2720169
10 32080501
11 416574212
12 5900292266
13 90461885331
14 1491788697451
15 26318520300986
16 494449968500832
17 9852544385880961
18 207497251731808341
19 4604297325494524516
20 107348917822006139114
21 2623224641748615607715
22 67035139167875735937219

List of values

[0, 1, 5, 20, 90, 499, 3395, 27474, 256984, 2720169, 32080501, 416574212, 5900292266, 90461885331, 1491788697451, 26318520300986, 494449968500832, 9852544385880961, 207497251731808341, 4604297325494524516, 107348917822006139114, 2623224641748615607715, 67035139167875735937219]

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

Content is available under The OEIS End-User License Agreement.