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.

A212405 Number of binary arrays of length 2*n+3 with no more than n ones in any length 2n subsequence (=50% duty cycle).

Table of values

n a(n)
1 13
2 57
3 236
4 959
5 3872
6 15586
7 62632
8 251419
9 1008536
10 4043582
11 16206152
12 64933782
13 260114976
14 1041797124
15 4171943056
16 16704821779
17 66880877896
18 267747443494
19 1071808583176
20 4290243456514
21 17172082337536
22 68729504287324

List of values

[13, 57, 236, 959, 3872, 15586, 62632, 251419, 1008536, 4043582, 16206152, 64933782, 260114976, 1041797124, 4171943056, 16704821779, 66880877896, 267747443494, 1071808583176, 4290243456514, 17172082337536, 68729504287324]

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

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