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.

A264521 Number of (3+1)X(n+1) arrays of permutations of 0..n*4+3 with each element having directed index change -1,0 0,2 -1,-2 or 1,0.

Table of values

n a(n)
1 1
2 3
3 9
4 42
5 196
6 644
7 2116
8 6854
9 22201
10 78076
11 274576
12 937960
13 3204100
14 10890360
15 37015056
16 126620208
17 433139344
18 1480295124
19 5059050129
20 17273618712
21 58979036736
22 201463380504
23 688168134481
24 2350844113032
25 8030694487104

List of values

[1, 3, 9, 42, 196, 644, 2116, 6854, 22201, 78076, 274576, 937960, 3204100, 10890360, 37015056, 126620208, 433139344, 1480295124, 5059050129, 17273618712, 58979036736, 201463380504, 688168134481, 2350844113032, 8030694487104]

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

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