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.

A027316 a(n) = Sum_{k=0..m-1} T(n,k) * T(n,k+1), where m=n for n=0,1,2,3; m=2n for n >= 4; and T is given by A026082.

Table of values

n a(n)
1 1
2 4
3 15
4 70
5 644
6 5502
7 46936
8 402164
9 3460536
10 29885592
11 258897792
12 2248831350
13 19579288052
14 170814593158
15 1492927792104
16 13069310259850
17 114576104658836
18 1005775588360122
19 8839355153926048
20 77768991557179442
21 684886480844420844
22 6037008171432448154

List of values

[1, 4, 15, 70, 644, 5502, 46936, 402164, 3460536, 29885592, 258897792, 2248831350, 19579288052, 170814593158, 1492927792104, 13069310259850, 114576104658836, 1005775588360122, 8839355153926048, 77768991557179442, 684886480844420844, 6037008171432448154]

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

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