A185926 Number of (n+1)X3 0..3 arrays with no 2X2 subblock trace equal to any horizontal or vertical neighbor 2X2 subblock trace

3392, 130944, 5113920, 199644672, 7794298816, 304295071104, 11879903064384, 463800149161728, 18107098487806016, 706914428967789184, 27598458655461285312, 1077464102208099420416, 42064990145791861161664

Offset

1,1

Comments

Column 2 of A185933

Links

R. H. Hardin, Table of n, a(n) for n = 1..185

Formula

Empirical: a(n)=15*a(n-1)+802*a(n-2)+5776*a(n-3)-13280*a(n-4)-165446*a(n-5)+218470*a(n-6)+1834338*a(n-7)-3769241*a(n-8)-5737257*a(n-9)+23686220*a(n-10)-22060678*a(n-11)-960030*a(n-12)+11338144*a(n-13)-3603928*a(n-14)-1266192*a(n-15)+533376*a(n-16)-43200*a(n-17)

Example

Some solutions for 5X3
..2..0..0....2..0..0....2..0..0....2..0..0....2..0..0....2..0..0....2..0..0
..0..0..0....0..0..0....2..0..0....2..0..0....0..0..0....0..0..0....2..0..0
..2..0..1....2..3..2....2..3..1....3..1..2....1..1..2....2..1..3....3..3..2
..2..3..3....1..2..0....0..1..2....2..3..3....1..1..3....2..1..0....0..3..0
..0..0..3....2..2..0....1..0..1....2..3..0....0..0..1....3..0..3....0..0..3

Crossrefs

Sequence in context: A262176 A172788 A185573 * A221009 A226667 A206507

Adjacent sequences: A185923 A185924 A185925 * A185927 A185928 A185929

Keyword

nonn

Author

R. H. Hardin Feb 06 2011

Status

approved