A303965 Number of nX4 0..1 arrays with every element unequal to 0, 1, 3 or 5 king-move adjacent elements, with upper left element zero.

5, 21, 26, 73, 173, 374, 842, 1923, 4326, 9786, 22216, 50282, 113823, 257876, 584048, 1322693, 2995970, 6785755, 15368972, 34809869, 78842537, 178572968, 404456933, 916071309, 2074845102, 4699397535, 10643852519, 24107680509, 54602433896

Offset

1,1

Comments

Column 4 of A303969.

Links

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

Formula

Empirical: a(n) = 2*a(n-1) +2*a(n-3) -a(n-4) -2*a(n-5) +7*a(n-6) -8*a(n-7) -2*a(n-8) -11*a(n-9) +a(n-10) +6*a(n-11) -12*a(n-12) +4*a(n-13) +4*a(n-14) +18*a(n-15) +7*a(n-16) -3*a(n-17) +6*a(n-18) +8*a(n-19) +2*a(n-20) -6*a(n-21) -10*a(n-22) -5*a(n-23) +a(n-24) -6*a(n-25) -6*a(n-26) -7*a(n-27) +a(n-28) +5*a(n-29) +2*a(n-32) +4*a(n-33) +2*a(n-34) -a(n-35) -a(n-36) for n>37

Example

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

Crossrefs

Cf. A303969.

Sequence in context: A042319 A302305 A351325 * A304351 A305914 A303036

Adjacent sequences: A303962 A303963 A303964 * A303966 A303967 A303968

Keyword

nonn

Author

R. H. Hardin, May 03 2018

Status

approved