A303892 Number of nX4 0..1 arrays with every element unequal to 1, 2, 3 or 4 king-move adjacent elements, with upper left element zero.

2, 86, 271, 1659, 7421, 39711, 195279, 1003855, 5056641, 25707978, 130248011, 660626529, 3350327180, 16988500456, 86159495911, 436909370593, 2215734673824, 11236289992560, 56982164600014, 288968180495974, 1465423301405206

Offset

1,1

Comments

Column 4 of A303896.

Links

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

Formula

Empirical: a(n) = 2*a(n-1) +22*a(n-2) -8*a(n-3) -131*a(n-4) +a(n-5) +153*a(n-6) -84*a(n-7) +542*a(n-8) +278*a(n-9) -1349*a(n-10) +447*a(n-11) +711*a(n-12) -308*a(n-13) +422*a(n-14) -2403*a(n-15) +1609*a(n-16) -250*a(n-17) -407*a(n-18) +3132*a(n-19) -3586*a(n-20) +3814*a(n-21) -3697*a(n-22) +375*a(n-23) +1563*a(n-24) -1317*a(n-25) +1526*a(n-26) -1386*a(n-27) +563*a(n-28) -422*a(n-29) +246*a(n-30) -59*a(n-31) +112*a(n-32) -21*a(n-33) -2*a(n-34) -7*a(n-35) for n>40

Example

Some solutions for n=5
..0..0..1..1. .0..0..1..0. .0..1..1..0. .0..1..0..0. .0..1..0..0
..0..1..1..0. .0..1..0..0. .0..0..0..1. .0..1..1..0. .0..1..1..0
..0..1..1..0. .1..1..1..0. .1..0..0..1. .1..1..1..1. .1..1..1..0
..0..1..1..0. .1..1..1..1. .1..0..0..1. .0..1..1..1. .0..1..0..0
..0..1..1..1. .0..1..1..0. .0..0..1..1. .0..0..0..1. .0..0..1..0

Crossrefs

Cf. A303896.

Sequence in context: A041881 A076542 A226842 * A305284 A304897 A316579

Adjacent sequences: A303889 A303890 A303891 * A303893 A303894 A303895

Keyword

nonn

Author

R. H. Hardin, May 02 2018

Status

approved