A229843 Number of nX4 0..2 arrays x(i,j) with each element horizontally or vertically next to at least one element with value 2-x(i,j).

9, 423, 13401, 453837, 15269193, 514371027, 17324310663, 583513743897, 19653679602141, 661968066724119, 22296164158938861, 750971189107675233, 25293934916476773699, 851940997449956765547, 28694762814404871782187

Offset: 1

Author

R. H. Hardin, Oct 01 2013

Keywords

• nonn

Comments

Column 4 of A229847

Examples

			Some solutions for n=3
..2..0..2..0....2..0..2..1....2..1..1..0....2..0..2..0....1..1..1..1
..2..2..2..2....1..0..0..1....0..0..2..2....0..0..2..1....2..0..2..0
..0..0..0..2....1..2..2..0....2..2..0..2....1..1..0..1....2..0..0..2
		

Links

• R. H. Hardin, Table of n, a(n) for n = 1..210

Formula

Empirical: a(n) = 28*a(n-1) +223*a(n-2) -810*a(n-3) -8714*a(n-4) -856*a(n-5) +147241*a(n-6) +236084*a(n-7) -1172242*a(n-8) -3528345*a(n-9) +678458*a(n-10) [phone]*a(n-11) [phone]*a(n-12) -128462366*a(n-13) -411090364*a(n-14) [phone]*a(n-15) -2603919959*a(n-16) [phone]*a(n-17) -7111289023*a(n-18) [phone]*a(n-19) -13438664953*a(n-20) [phone]*a(n-21) -17181774335*a(n-22) [phone]*a(n-23) -15592749244*a(n-24) [phone]*a(n-25) [phone]*a(n-26) -3292600679*a(n-27) [phone]*a(n-28) -4461452087*a(n-29) -11101458512*a(n-30) [phone]*a(n-31) -67227775904*a(n-32) [phone]*a(n-33) -116673702936*a(n-34) [phone]*a(n-35) -123437354031*a(n-36) [phone]*a(n-37) -110378277541*a(n-38) [phone]*a(n-39) -80590207954*a(n-40) [phone]*a(n-41) -49928847307*a(n-42) [phone]*a(n-43) -25484291913*a(n-44) [phone]*a(n-45) -10724796799*a(n-46) [phone]*a(n-47) -4421780238*a(n-48) [phone]*a(n-49) -1102876952*a(n-50) [phone]*a(n-51) -116104448*a(n-52) -5874816*a(n-53)