A281327 Number of 2Xn 0..2 arrays with no element equal to more than one of its horizontal and antidiagonal neighbors, with the exception of exactly one element, and with new values introduced in order 0 sequentially upwards.

0, 2, 46, 394, 3102, 22342, 153982, 1028164, 6712782, 43087434, 272912970, 1710241966, 10623835430, 65512041216, 401476483174, 2447254681866, 14848545047958, 89727018732086, 540259780322574, 3242602059388124

Offset

1,2

Comments

Row 2 of A281326.

Links

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

Formula

Empirical: a(n) = 10*a(n-1) -13*a(n-2) -82*a(n-3) +60*a(n-4) +210*a(n-5) -77*a(n-6) -202*a(n-7) +39*a(n-8) +56*a(n-9) -16*a(n-10) for n>11

Example

Some solutions for n=4
..0..1..2..1. .0..0..1..2. .0..1..0..2. .0..1..2..0. .0..1..2..0
..1..1..0..0. .0..2..1..0. .2..0..0..1. .1..1..0..2. .2..2..0..2

Crossrefs

Cf. A281326.

Sequence in context: A071777 A179108 A158960 * A302377 A303098 A377840

Adjacent sequences: A281324 A281325 A281326 * A281328 A281329 A281330

Keyword

nonn

Author

R. H. Hardin, Jan 20 2017

Status

approved