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.

A092285 Number of productions of a certain "divide-and-conquer" context-free grammar in Chomsky normal form that generates all permutations of n symbols.

Table of values

n a(n)
1 1
2 4
3 12
4 22
5 65
6 116
7 399
8 554
9 2475
10 3232
11 14938
12 20208
13 101413
14 130846
15 691890
16 924946
17 4867559
18 6281552
19 35154066
20 46902128
21 253485141
22 328375720
23 1877693458
24 2504042868
25 13754442225
26 17885555976
27 103317302754
28 137761862662
29 765705075439
30 998817493980

List of values

[1, 4, 12, 22, 65, 116, 399, 554, 2475, 3232, 14938, 20208, 101413, 130846, 691890, 924946, 4867559, 6281552, 35154066, 46902128, 253485141, 328375720, 1877693458, 2504042868, 13754442225, 17885555976, 103317302754, 137761862662, 765705075439, 998817493980]

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

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