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A269055
Number of 4Xn 0..2 arrays with some element plus some horizontally, diagonally or antidiagonally adjacent neighbor totalling two not more than once.
1
81, 666, 3258, 24192, 149358, 971844, 6053094, 37741920, 231943614, 1417576284, 8599619586, 51899214960, 311654917170, 1863739501308, 11103704855298, 65935768579488, 390381077316294, 2305171593612444, 13579182450069246
OFFSET
1,1
COMMENTS
Row 4 of A269052.
LINKS
FORMULA
Empirical: a(n) = 6*a(n-1) +23*a(n-2) -102*a(n-3) -288*a(n-4) +250*a(n-5) +787*a(n-6) -238*a(n-7) -741*a(n-8) +124*a(n-9) +196*a(n-10) -16*a(n-11) -16*a(n-12) for n>14
EXAMPLE
Some solutions for n=4
..0..0..1..2. .1..2..1..0. .1..2..1..0. .2..2..2..2. .1..0..1..2
..1..0..1..0. .0..0..1..0. .2..2..2..2. .2..2..1..0. .1..2..1..2
..1..2..1..2. .1..0..1..0. .2..1..2..1. .2..2..1..0. .2..2..2..2
..1..0..2..2. .1..0..0..0. .2..1..0..1. .1..2..1..2. .1..1..2..1
CROSSREFS
Cf. A269052.
Sequence in context: A236720 A187441 A187433 * A236876 A185366 A232026
KEYWORD
nonn
AUTHOR
R. H. Hardin, Feb 18 2016
STATUS
approved