A186880 - OEIS

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A186880

Number of (n+2)X10 0..3 arrays with every 3X3 subblock commuting with each horizontal and vertical neighbor 3X3 subblock

322910, 25381, 46624, 148048, 310528, 414184, 571984, 801208, 1130584, 1842208, 3014488, 4813744, 8147608, 13457800, 21637048, 37154419, 62117614, 101085745, 172069837, 287321977, 469126669, 793531357, 1325629774, 2174290240

(list; graph; refs; listen; history; text; internal format)

OFFSET

1,1

COMMENTS

Column 8 of A186881

LINKS

R. H. Hardin, Table of n, a(n) for n = 1..200

FORMULA

Empirical: a(n)=2*a(n-1)-a(n-2)+3*a(n-3)-6*a(n-4)+3*a(n-5)+3*a(n-6)-3*a(n-7) for n>16

EXAMPLE

Some solutions for 4X10

..0..0..3..0..0..0..0..0..0..1....0..0..0..0..0..0..0..0..3..0