A317379 Number of nX4 0..1 arrays with every element unequal to 0, 1, 2, 5, 6, 7 or 8 king-move adjacent elements, with upper left element zero.

8, 9, 36, 123, 414, 1580, 5704, 20162, 72715, 262549, 944628, 3399508, 12242821, 44087164, 158739670, 571576721, 2058142185, 7410913041, 26684956759, 96086522975, 345986123562, 1245818108353, 4485910314885, 16152754437159

Offset

1,1

Comments

Column 4 of A317383.

Links

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

Formula

Empirical: a(n) = 2*a(n-1) +6*a(n-2) +4*a(n-3) -6*a(n-4) -32*a(n-5) -43*a(n-6) +7*a(n-7) +82*a(n-8) +59*a(n-9) +16*a(n-10) +10*a(n-11) -62*a(n-12) -69*a(n-13) -24*a(n-14) -7*a(n-15) +24*a(n-16) +34*a(n-17) +8*a(n-18) -8*a(n-19) for n>23

Example

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

Crossrefs

Cf. A317383.

Sequence in context: A129548 A322797 A075079 * A298665 A284822 A222354

Adjacent sequences: A317376 A317377 A317378 * A317380 A317381 A317382

Keyword

nonn

Author

R. H. Hardin, Jul 26 2018

Status

approved