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.

A006958 Number of parallelogram polyominoes with n cells (also called staircase polyominoes, although that term is overused).

Table of values

n a(n)
1 1
2 2
3 4
4 9
5 20
6 46
7 105
8 242
9 557
10 1285
11 2964
12 6842
13 15793
14 36463
15 84187
16 194388
17 448847
18 1036426
19 2393208
20 5526198
21 12760671
22 29466050
23 68041019
24 157115917
25 362802072
26 837759792
27 1934502740
28 4467033943
29 10314998977
30 23818760154
31 55000815222
32 127004500762

List of values

[1, 2, 4, 9, 20, 46, 105, 242, 557, 1285, 2964, 6842, 15793, 36463, 84187, 194388, 448847, 1036426, 2393208, 5526198, 12760671, 29466050, 68041019, 157115917, 362802072, 837759792, 1934502740, 4467033943, 10314998977, 23818760154, 55000815222, 127004500762]

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

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