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.

A227035 a(n) = Sum_{k=0..floor(n/4)} binomial(n,4*k)*binomial(5*k,k)/(4*k+1).

Table of values

n a(n)
0 1
1 1
2 1
3 1
4 2
5 6
6 16
7 36
8 76
9 172
10 436
11 1156
12 3006
13 7606
14 19202
15 49466
16 130156
17 345356
18 915196
19 2421532
20 6427001
21 17163581
22 46087911
23 124133531
24 334850208
25 904691576
26 2449891276
27 6651540676
28 18100561856
29 49344295152
30 134719523056
31 368350942416
32 1008680051756

List of values

[1, 1, 1, 1, 2, 6, 16, 36, 76, 172, 436, 1156, 3006, 7606, 19202, 49466, 130156, 345356, 915196, 2421532, 6427001, 17163581, 46087911, 124133531, 334850208, 904691576, 2449891276, 6651540676, 18100561856, 49344295152, 134719523056, 368350942416, 1008680051756]

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

Content is available under The OEIS End-User License Agreement.