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.

A378907 Number of permutations of [n] with at least one hit on both main diagonals.

Table of values

n a(n)
0 0
1 1
2 0
3 2
4 10
5 48
6 270
7 2004
8 15406
9 144656
10 1399070
11 15924940
12 185817038
13 2485431096
14 33966603790
15 522088434644
16 8178526719550
17 142034596036896
18 2508925152633918
19 48582127821078684
20 955299461042098222
21 20406401587894276040
22 442067447198146300718

List of values

[0, 1, 0, 2, 10, 48, 270, 2004, 15406, 144656, 1399070, 15924940, 185817038, 2485431096, 33966603790, 522088434644, 8178526719550, 142034596036896, 2508925152633918, 48582127821078684, 955299461042098222, 20406401587894276040, 442067447198146300718]

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

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