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.

A200866 Number of 0..3 arrays x(0..n+1) of n+2 elements without any interior element greater than both neighbors or less than both neighbors.

Table of values

n a(n)
1 36
2 94
3 236
4 602
5 1528
6 3882
7 9858
8 25038
9 63592
10 161514
11 410218
12 1041884
13 2646208
14 6720920
15 17069998
16 43354902
17 110114102
18 279671154
19 710317326
20 1804085608
21 4582071648
22 11637685314
23 29557748082
24 75071670020
25 190669317026
26 484267746348
27 1229957991200
28 3123884816870

List of values

[36, 94, 236, 602, 1528, 3882, 9858, 25038, 63592, 161514, 410218, 1041884, 2646208, 6720920, 17069998, 43354902, 110114102, 279671154, 710317326, 1804085608, 4582071648, 11637685314, 29557748082, 75071670020, 190669317026, 484267746348, 1229957991200, 3123884816870]

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

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