A183477 Number of nX3 0..2 arrays with every element equal to either the sum mod 3 of its vertical neighbors or the sum mod 3 of its horizontal neighbors.

5, 39, 117, 587, 2925, 12131, 58333, 270611, 1220877, 5724163, 26403017, 121544939, 564597457, 2608586447, 12062272841, 55880316803, 258485374601, 1196311279235, 5538446306557, 25631318490835, 118643423750561, 549199683026799

Offset: 1

Author

R. H. Hardin Jan 05 2011

Keywords

• nonn

Comments

Column 3 of A183483

Examples

			Some solutions for 4X3
..1..1..0....1..1..1....0..2..2....1..1..0....1..1..0....2..2..0....1..1..0
..1..1..0....1..1..0....0..0..0....1..1..0....1..1..0....0..0..0....1..1..0
..1..1..0....2..2..2....1..0..2....0..0..0....2..2..0....1..0..0....0..0..0
..1..1..0....2..1..2....1..0..2....0..0..0....2..2..0....1..0..0....2..2..0
		

Links

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

Formula

Empirical: a(n)=8*a(n-1)-18*a(n-2)+84*a(n-3)-579*a(n-4)+1348*a(n-5)-3464*a(n-6)+18376*a(n-7)-41015*a(n-8)+79527*a(n-9)-334512*a(n-10)+695496*a(n-11)-1111399*a(n-12)+3876831*a(n-13)-7441854*a(n-14)[phone]*a(n-15)-30655065*a(n-16)[phone]*a(n-17)-64701205*a(n-18)[phone]*a(n-19)-281900303*a(n-20)[phone]*a(n-21)-730333225*a(n-22)[phone]*a(n-23)-1011789825*a(n-24)[phone]*a(n-25)-3177451713*a(n-26)[phone]*a(n-27)-5787685442*a(n-28)[phone]*a(n-29)-5223552815*a(n-30)[phone]*a(n-31)-12673488056*a(n-32)[phone]*a(n-33)-17162050486*a(n-34)[phone]*a(n-35)-9768296437*a(n-36)[phone]*a(n-37)-19224576837*a(n-38)[phone]*a(n-39)-19470134294*a(n-40)[phone]*a(n-41)-6427344807*a(n-42)[phone]*a(n-43)-10725609446*a(n-44)[phone]*a(n-45)-7805973809*a(n-46)[phone]*a(n-47)-1227503579*a(n-48)[phone]*a(n-49)-1907177092*a(n-50)[phone]*a(n-51)-900778627*a(n-52)[phone]*a(n-53)-34626683*a(n-54)[phone]*a(n-55)-80150140*a(n-56)-3548276*a(n-57)-16126436*a(n-58)+7908948*a(n-59)+2463356*a(n-60)+267632*a(n-61)-411136*a(n-62)-464048*a(n-63)+49264*a(n-64)+9792*a(n-65)+28416*a(n-66)