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.

A222204 Write n=3i+j, 0<=j<3; a(n) = number of ways to cover the r X s grid graph by vertex disjoint cycles, where (r,s) = (2i+2, 2i+2) (if j=0), (2i+2, 2i+3) (if j=1) or (2i+3, 2i+4) (if j=2).

Table of values

n a(n)
0 1
1 1
2 3
3 18
4 54
5 1140
6 13903
7 99051
8 13049563
9 360783593
10 6044482889
11 4738211572702
12 303872744726644
13 11986520595161863
14 54755153078468134960
15 8217125138015950451626
16 764291947227525464744293
17 20119942924108379011391597989
18 7095967027221343377167292602835
19 1558052539448513320447263528275071

List of values

[1, 1, 3, 18, 54, 1140, 13903, 99051, 13049563, 360783593, 6044482889, 4738211572702, 303872744726644, 11986520595161863, 54755153078468134960, 8217125138015950451626, 764291947227525464744293, 20119942924108379011391597989, 7095967027221343377167292602835, 1558052539448513320447263528275071]