A186135 Number of (n+1)X4 0..2 arrays with no 2X2 subblock trace equal to any horizontal or vertical neighbor 2X2 subblock trace

3888, 107874, 3090564, 88110594, 2513594016, 71683161894, 2044563391476, 58311925687818, 1663128694130598, 47433932055670734, 1352865880643114214, 38585070116572714902, 1100485517204049090894, 31386952148587046019792

Offset

1,1

Comments

Column 3 of A186141

Links

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

Formula

Empirical: a(n)=8*a(n-1)+551*a(n-2)+2092*a(n-3)-29959*a(n-4)-80288*a(n-5)+807333*a(n-6)+327072*a(n-7)-9377682*a(n-8)+9809631*a(n-9)+37995967*a(n-10)-77988412*a(n-11)-25468024*a(n-12)+142020278*a(n-13)-6381828*a(n-14)-124693659*a(n-15)-23375996*a(n-16)+64568471*a(n-17)+52421184*a(n-18)-6894001*a(n-19)-26781500*a(n-20)-12165465*a(n-21)+158720*a(n-22)+3261613*a(n-23)+1589010*a(n-24)+560063*a(n-25)+355508*a(n-26)+79536*a(n-27)+6024*a(n-28)+5184*a(n-29) for n>30

Example

Some solutions for 3X4
..1..1..2..0....1..1..0..1....0..0..2..0....1..2..0..2....2..0..0..1
..1..1..0..1....1..1..0..2....0..2..0..0....0..1..1..0....1..1..0..2
..2..0..2..1....1..2..1..0....0..0..1..0....0..0..0..1....1..1..2..0

Crossrefs

Sequence in context: A014891 A253484 A253479 * A223597 A223438 A223690

Adjacent sequences: A186132 A186133 A186134 * A186136 A186137 A186138

Keyword

nonn

Author

R. H. Hardin Feb 13 2011

Status

approved