A281029 Number of nX3 0..1 arrays with no element equal to more than three of its king-move neighbors, with the exception of exactly one element, and with new values introduced in order 0 sequentially upwards.

0, 2, 96, 532, 2321, 8886, 31700, 108034, 357542, 1158596, 3694697, 11633400, 36255175, 112035020, 343760934, 1048431286, 3181035325, 9608044744, 28905403029, 86656025654, 258976361436, 771797361724, 2294287282225

Offset

1,2

Comments

Column 3 of A281034.

Links

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

Formula

Empirical: a(n) = 6*a(n-1) -11*a(n-2) +4*a(n-3) +19*a(n-4) -46*a(n-5) +23*a(n-6) +4*a(n-7) -59*a(n-8) +26*a(n-9) -37*a(n-10) -20*a(n-11) +4*a(n-12) -36*a(n-13) -8*a(n-15) -8*a(n-16) -4*a(n-18) for n>21

Example

Some solutions for n=4
..0..0..0. .0..1..0. .0..0..1. .0..0..1. .0..0..0. .0..1..0. .0..1..0
..0..1..0. .1..1..1. .0..1..1. .1..0..1. .0..1..0. .0..0..0. .0..1..0
..0..1..0. .1..0..0. .1..0..1. .1..1..1. .0..1..1. .1..1..1. .1..0..1
..1..0..1. .1..0..0. .0..1..0. .0..0..1. .1..0..0. .0..0..1. .0..0..1

Crossrefs

Cf. A281034.

Sequence in context: A346654 A324165 A266831 * A282436 A069121 A362406

Adjacent sequences: A281026 A281027 A281028 * A281030 A281031 A281032

Keyword

nonn

Author

R. H. Hardin, Jan 13 2017

Status

approved