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.

A305778 Number of set partitions of [n] with alternating parity of elements and exactly four blocks.

Table of values

n a(n)
4 1
5 4
6 12
7 33
8 84
9 222
10 545
11 1425
12 3458
13 8948
14 21595
15 55335
16 133144
17 338530
18 813249
19 2056245
20 4935870
21 12432432
22 29833463
23 74952867
24 179842724
25 451071998
26 1082309293
27 2711584785
28 6506473162
29 16289249356
30 39088013091
31 97811687679
32 234720639024
33 587166227226

List of values

[1, 4, 12, 33, 84, 222, 545, 1425, 3458, 8948, 21595, 55335, 133144, 338530, 813249, 2056245, 4935870, 12432432, 29833463, 74952867, 179842724, 451071998, 1082309293, 2711584785, 6506473162, 16289249356, 39088013091, 97811687679, 234720639024, 587166227226]

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

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