A298384 Number of nX3 0..1 arrays with every element equal to 1, 2, 3, 5 or 6 king-move adjacent elements, with upper left element zero.

1, 18, 56, 223, 849, 3387, 13075, 51006, 199243, 777845, 3035261, 11848853, 46252538, 180542983, 704739373, 2750937235, 10738195965, 41916200522, 163618636603, 638680511133, 2493070208921, 9731625088447, 37987108531520

Offset

1,2

Comments

Column 3 of A298389.

Links

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

Formula

Empirical: a(n) = 4*a(n-1) +4*a(n-3) -17*a(n-4) -25*a(n-5) +23*a(n-6) +33*a(n-7) +41*a(n-8) -145*a(n-9) -147*a(n-10) +24*a(n-11) +384*a(n-12) +267*a(n-13) -72*a(n-14) -207*a(n-15) -61*a(n-16) +51*a(n-17) +10*a(n-18) -14*a(n-19) -4*a(n-20) for n>21

Example

Some solutions for n=7
..0..0..0. .0..0..0. .0..0..1. .0..0..0. .0..1..0. .0..1..1. .0..1..0
..0..0..0. .1..1..1. .1..0..1. .1..0..1. .1..0..0. .0..1..0. .0..1..0
..1..1..1. .0..1..0. .1..0..1. .1..1..1. .0..0..1. .0..1..0. .1..0..1
..0..0..0. .1..0..1. .0..1..0. .1..0..1. .1..1..1. .1..1..0. .0..0..0
..1..0..1. .0..0..0. .1..0..0. .0..1..0. .0..0..0. .0..0..1. .1..1..1
..0..1..0. .1..1..1. .1..1..1. .0..1..0. .1..1..1. .1..1..0. .0..0..0
..0..0..1. .1..1..1. .0..0..0. .0..1..0. .0..0..1. .0..0..0. .0..0..0

Crossrefs

Cf. A298389.

Sequence in context: A044975 A251252 A297946 * A298765 A299460 A155155

Adjacent sequences: A298381 A298382 A298383 * A298385 A298386 A298387

Keyword

nonn

Author

R. H. Hardin, Jan 18 2018

Status

approved