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.

A151645 Number of permutations of 4 indistinguishable copies of 1..n with exactly 7 adjacent element pairs in decreasing order.

Table of values

n a(n)
1 0
2 0
3 112
4 15018688
5 69830127680
6 99825129369600
7 79985306860607376
8 46314409921814756480
9 22045769335091544766944
10 9274231983519733250418880
11 3600979296578512256763795120
12 1326029824370661243342378614592
13 471290654822091236131899199410048

List of values

[0, 0, 112, 15018688, 69830127680, 99825129369600, 79985306860607376, 46314409921814756480, 22045769335091544766944, 9274231983519733250418880, 3600979296578512256763795120, 1326029824370661243342378614592, 471290654822091236131899199410048]

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

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