A184381 1/12 the number of (n+2)X6 0..2 arrays with each 3X3 subblock containing three of each value

9113, 13616, 21473, 38642, 104312, 336236, 1348574, 6736118, 35668172, 198726728, 1153450280, 6759631310, 39967552418, 238155498086, 1421741546408, 8502748040192, 50935935695672, 305257947824246, 1830140712020354

Offset

1,1

Comments

Column 4 of A184386

Links

R. H. Hardin, Table of n, a(n) for n = 1..74

Formula

Empirical: a(n)=12*a(n-1)-47*a(n-2)+186*a(n-3)-1404*a(n-4)+5358*a(n-5)-12815*a(n-6)+59388*a(n-7)-216529*a(n-8)+421074*a(n-9)-1238292*a(n-10)+4200390*a(n-11)-7370532*a(n-12)+14448024*a(n-13)-43986924*a(n-14)+72896760*a(n-15)-99842544*a(n-16)+259089192*a(n-17)-414953280*a(n-18)+415059552*a(n-19)-848382336*a(n-20)+1329975936*a(n-21)-1013741568*a(n-22)+1425340800*a(n-23)-2203656192*a(n-24)+1333615104*a(n-25)-947303424*a(n-26)+1451188224*a(n-27)-725594112*a(n-28)

Example

Some solutions with a(1,1)=0 for 4X6
..0..2..2..0..1..2....0..1..2..0..1..2....0..2..2..1..2..2....0..1..0..0..1..2
..1..1..0..1..2..0....1..0..2..2..0..2....1..0..1..0..2..1....0..2..2..0..1..0
..1..0..2..1..0..2....2..0..1..1..0..1....1..2..0..1..0..0....2..1..1..2..2..1
..2..2..0..2..1..0....1..2..0..1..2..0....0..2..2..1..2..2....0..1..0..0..1..2

Crossrefs

Sequence in context: A157619 A233713 A174983 * A251376 A253031 A093213

Adjacent sequences: A184378 A184379 A184380 * A184382 A184383 A184384

Keyword

nonn

Author

R. H. Hardin Jan 12 2011

Status

approved