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.

A334412 Number of ordered pairs of permutations of [n] avoiding synchronous double descent pairs.

Table of values

n a(n)
0 1
1 1
2 4
3 35
4 545
5 13250
6 463899
7 22106253
8 1375915620
9 108386009099
10 10540705282001
11 1240370638524842
12 173704235075714947
13 28549174106487593365
14 5441843626292088857818
15 1190762128123996264128849
16 296456799935194225886732961
17 83321234634397591315509479058

List of values

[1, 1, 4, 35, 545, 13250, 463899, 22106253, 1375915620, 108386009099, 10540705282001, 1240370638524842, 173704235075714947, 28549174106487593365, 5441843626292088857818, 1190762128123996264128849, 296456799935194225886732961, 83321234634397591315509479058]

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

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