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.

A090460 Number of essentially different permutations of the numbers 1 to n such that the sum of adjacent numbers is a square.

Table of values

n a(n)
15 1
16 1
17 1
18 0
19 0
20 0
21 0
22 0
23 3
24 0
25 10
26 12
27 35
28 52
29 19
30 20
31 349
32 361
33 637
34 3678
35 15237
36 11875
37 13306
38 10964
39 27223
40 37054
41 201408
42 510152
43 1995949
44 4867214
45 11255174
46 35705858
47 63029611
48 129860749
49 258247089
50 190294696
51 686125836
52 2195910738
53 5114909395
54 9141343219
55 19769529758
56 44678128099
57 63885400119

List of values

[1, 1, 1, 0, 0, 0, 0, 0, 3, 0, 10, 12, 35, 52, 19, 20, 349, 361, 637, 3678, 15237, 11875, 13306, 10964, 27223, 37054, 201408, 510152, 1995949, 4867214, 11255174, 35705858, 63029611, 129860749, 258247089, 190294696, 686125836, 2195910738, 5114909395, 9141343219, 19769529758, 44678128099, 63885400119]

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

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