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.

A005270 Number of sequences s of length n with s[1]=1, s[2]=1, s[j-1] for j>=3.

Table of values

n a(n)
2 1
3 1
4 1
5 2
6 6
7 27
8 177
9 1680
10 23009
11 455368
12 13067353
13 546378617
14 33472296082
15 3021920660821
16 404374532614122
17 80646410554881100
18 24095492607316134304
19 10837141045948365696938
20 7369252748590790186483284
21 7606603491185739308318700818

List of values

[1, 1, 1, 2, 6, 27, 177, 1680, 23009, 455368, 13067353, 546378617, 33472296082, 3021920660821, 404374532614122, 80646410554881100, 24095492607316134304, 10837141045948365696938, 7369252748590790186483284, 7606603491185739308318700818]

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

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