A281247 - OEIS

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A281247

Number of nX2 0..2 arrays with no element equal to more than one of its horizontal, vertical and antidiagonal neighbors, with the exception of exactly two elements, and with new values introduced in order 0 sequentially upwards.

0, 0, 12, 139, 1222, 9151, 63138, 412070, 2585022, 15739317, 93614462, 546390377, 3139809956, 17808523566, 99888570784, 554920263375, 3057078206870, 16717853840323, 90826885281558, 490581957118358, 2635899256765106

(list; graph; refs; listen; history; text; internal format)

OFFSET

1,3

COMMENTS

Column 2 of A281251.

LINKS

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

FORMULA

Empirical: a(n) = 13*a(n-1) -48*a(n-2) +7*a(n-3) +149*a(n-4) +96*a(n-5) -59*a(n-6) -97*a(n-7) -48*a(n-8) -11*a(n-9) -a(n-10) for n>12

EXAMPLE

Some solutions for n=4

..0..1. .0..1. .0..1. .0..1. .0..1. .0..0. .0..1. .0..1. .0..0. .0..0