A306049 Number of nX4 0..1 arrays with every element unequal to 0, 1, 2, 3, 6 or 7 king-move adjacent elements, with upper left element zero.

8, 49, 142, 458, 1962, 6604, 22446, 86464, 311891, 1100642, 4051876, 14751188, 52994208, 192694281, 700643032, 2533737542, 9188792804, 33358655064, 120883510481, 438255796512, 1589816384928, 5764235810314, 20899418376356

Offset

1,1

Comments

Column 4 of A306053.

Links

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

Formula

Empirical: a(n) = 7*a(n-1) -17*a(n-2) +39*a(n-3) -133*a(n-4) +234*a(n-5) -178*a(n-6) +296*a(n-7) -581*a(n-8) +168*a(n-9) +290*a(n-10) +137*a(n-11) -67*a(n-12) -620*a(n-13) +433*a(n-14) -15*a(n-15) +166*a(n-16) -206*a(n-17) +44*a(n-18) -6*a(n-19) +14*a(n-20) -4*a(n-21) for n>25

Example

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

Crossrefs

Cf. A306053.

Sequence in context: A272713 A316285 A018200 * A317226 A329051 A295777

Adjacent sequences: A306046 A306047 A306048 * A306050 A306051 A306052

Keyword

nonn

Author

R. H. Hardin, Jun 18 2018

Status

approved