A302362 - OEIS

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A302362

Number of nX3 0..1 arrays with every element equal to 0, 2, 3 or 4 horizontally, diagonally or antidiagonally adjacent elements, with upper left element zero.

1, 12, 31, 109, 397, 1430, 5110, 18395, 66203, 238103, 856413, 3081033, 11083994, 39873749, 143444250, 516038048, 1856433397, 6678469130, 24025629692, 86431623758, 310935653685, 1118583441105, 4024076800534, 14476518656548

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

OFFSET

1,2

COMMENTS

Column 3 of A302367.

LINKS

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

FORMULA

Empirical: a(n) = 4*a(n-1) -3*a(n-2) +9*a(n-3) -9*a(n-4) -11*a(n-5) +a(n-6) -18*a(n-7) +16*a(n-8) -12*a(n-9) -4*a(n-10) +4*a(n-11) +8*a(n-12)

EXAMPLE

Some solutions for n=5

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