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.

A206948 Number of nonisomorphic graded posets with 0 and non-uniform Hasse graph of rank n, with exactly 2 elements of each rank level above 0.

Table of values

n a(n)
0 0
1 0
2 0
3 2
4 19
5 131
6 791
7 4446
8 23913
9 124892
10 638878
11 3218559
12 16027375
13 79093773
14 387540260
15 1887974063
16 9154751912
17 44221373872
18 212931964415
19 1022594028515
20 4900116587043
21 23437066655010
22 111923110602497

List of values

[0, 0, 0, 2, 19, 131, 791, 4446, 23913, 124892, 638878, 3218559, 16027375, 79093773, 387540260, 1887974063, 9154751912, 44221373872, 212931964415, 1022594028515, 4900116587043, 23437066655010, 111923110602497]

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

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