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.

A180789 Number of distinct solutions of sum{i=1..7}(x(2i-1)*x(2i)) = 1 (mod n), with x() only in 1..n-1.

Table of values

n a(n)
1 0
2 1
3 15
4 198
5 2282
6 19300
7 126861
8 670058
9 2997685
10 11539243
11 39660969
12 122371876
13 348412793
14 914595808
15 2264326584
16 5259342780
17 11692554312
18 24683815072
19 50403390786
20 98560661538
21 187881799209
22 345060981679
23 621482071341

List of values

[0, 1, 15, 198, 2282, 19300, 126861, 670058, 2997685, 11539243, 39660969, 122371876, 348412793, 914595808, 2264326584, 5259342780, 11692554312, 24683815072, 50403390786, 98560661538, 187881799209, 345060981679, 621482071341]

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

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