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A281055
Number of nX7 0..1 arrays with no element equal to more than one of its horizontal and antidiagonal neighbors, with the exception of exactly two elements, and with new values introduced in order 0 sequentially upwards.
1
13, 535, 2828, 10570, 32370, 87995, 221212, 526340, 1201939, 2661939, 5752796, 12190173, 25413086, 52258597, 106216045, 213723050, 426288170, 843735147, 1658596579, 3240610144, 6297012052, 12175728717, 23437264280, 44930659786
OFFSET
1,1
COMMENTS
Column 7 of A281056.
LINKS
FORMULA
Empirical: a(n) = 5*a(n-1) -6*a(n-2) -4*a(n-3) +5*a(n-4) +9*a(n-5) -3*a(n-6) -3*a(n-7) -3*a(n-8) -9*a(n-9) +6*a(n-11) +8*a(n-12) +2*a(n-13) +3*a(n-14) -3*a(n-15) -3*a(n-16) -3*a(n-17) -a(n-18) -a(n-19) for n>23
EXAMPLE
Some solutions for n=4
..0..1..0..1..0..0..1. .0..1..1..1..0..1..0. .0..1..0..1..1..1..0
..0..1..0..1..1..0..1. .0..1..0..1..0..1..0. .0..1..0..1..0..0..1
..0..1..0..0..1..0..1. .0..1..0..1..0..1..0. .0..1..0..1..1..0..1
..0..1..1..1..1..0..1. .1..0..1..0..1..1..0. .0..1..0..0..1..0..0
CROSSREFS
Cf. A281056.
Sequence in context: A300525 A295942 A297518 * A030256 A023332 A309204
KEYWORD
nonn
AUTHOR
R. H. Hardin, Jan 13 2017
STATUS
approved