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.

A248836 Number of length n arrays x(i), i=1..n with x(i) in 0..i and no value appearing more than 2 times.

Table of values

n a(n)
0 1
1 2
2 6
3 22
4 96
5 482
6 2736
7 17302
8 120576
9 917762
10 7574016
11 67354582
12 642041856
13 6530291042
14 70589700096
15 808090395862
16 9766250151936
17 124258689304322
18 1660195646078976
19 23239748527125142
20 340125128186658816
21 5194627679316741602
22 82645634692238278656

List of values

[1, 2, 6, 22, 96, 482, 2736, 17302, 120576, 917762, 7574016, 67354582, 642041856, 6530291042, 70589700096, 808090395862, 9766250151936, 124258689304322, 1660195646078976, 23239748527125142, 340125128186658816, 5194627679316741602, 82645634692238278656]

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

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