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.

A187984 Number of nondecreasing arrangements of n numbers x(i) in -(n+3)..(n+3) with the sum of sign(x(i))*2^|x(i)| zero.

Table of values

n a(n)
1 0
2 5
3 11
4 39
5 144
6 467
7 1673
8 5825
9 20404
10 72246
11 255137
12 905611
13 3220635
14 11472797
15 40956011
16 146412581
17 524169045
18 1878990744
19 6743276222
20 24225861208
21 87117117408
22 313552816720
23 1129460906243
24 4071526431770
25 14687417557462
26 53016891233217
27 191489301052386
28 692020548649474
29 2502200138127277
30 9051895373199102
31 32761105883346693

List of values

[0, 5, 11, 39, 144, 467, 1673, 5825, 20404, 72246, 255137, 905611, 3220635, 11472797, 40956011, 146412581, 524169045, 1878990744, 6743276222, 24225861208, 87117117408, 313552816720, 1129460906243, 4071526431770, 14687417557462, 53016891233217, 191489301052386, 692020548649474, 2502200138127277, 9051895373199102, 32761105883346693]

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

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