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.

A189491 Number of arrangements of n+1 nonzero numbers x(i) in -2..2 with the sum of floor(x(i)/x(i+1)) equal to zero.

Table of values

n a(n)
1 2
2 12
3 42
4 136
5 550
6 1892
7 7384
8 26816
9 103288
10 386928
11 1485566
12 5654000
13 21736466
14 83448592
15 321767288
16 1241835856
17 4803432344
18 18605438864
19 72168550344
20 280295950240
21 1089835505354
22 4242072071396
23 16526909026016
24 64446293812896

List of values

[2, 12, 42, 136, 550, 1892, 7384, 26816, 103288, 386928, 1485566, 5654000, 21736466, 83448592, 321767288, 1241835856, 4803432344, 18605438864, 72168550344, 280295950240, 1089835505354, 4242072071396, 16526909026016, 64446293812896]

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

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