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.

A203286 Number of arrays of 2n nondecreasing integers in -3..3 with sum zero and equal numbers greater than zero and less than zero.

Table of values

n a(n)
1 4
2 12
3 28
4 57
5 104
6 176
7 280
8 425
9 620
10 876
11 1204
12 1617
13 2128
14 2752
15 3504
16 4401
17 5460
18 6700
19 8140
20 9801
21 11704
22 13872
23 16328
24 19097
25 22204
26 25676
27 29540
28 33825
29 38560
30 43776
31 49504
32 55777
33 62628
34 70092
35 78204
36 87001
37 96520
38 106800
39 117880
40 129801

List of values

[4, 12, 28, 57, 104, 176, 280, 425, 620, 876, 1204, 1617, 2128, 2752, 3504, 4401, 5460, 6700, 8140, 9801, 11704, 13872, 16328, 19097, 22204, 25676, 29540, 33825, 38560, 43776, 49504, 55777, 62628, 70092, 78204, 87001, 96520, 106800, 117880, 129801]

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

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