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A283785
Number of 2Xn 0..1 arrays with no 1 equal to more than two of its horizontal, diagonal and antidiagonal neighbors, with the exception of exactly two elements.
1
0, 0, 5, 14, 113, 564, 2410, 10648, 45070, 183756, 737827, 2915310, 11349831, 43690696, 166558192, 629523408, 2361726556, 8802501992, 32617430417, 120233967102, 441127508365, 1611581366764, 5864853582278, 21267822706488
OFFSET
1,3
COMMENTS
Row 2 of A283784.
LINKS
FORMULA
Empirical: a(n) = 9*a(n-1) -24*a(n-2) +18*a(n-3) -48*a(n-4) +156*a(n-5) +46*a(n-6) -78*a(n-7) -423*a(n-8) -501*a(n-9) +474*a(n-10) +972*a(n-11) +840*a(n-12) -288*a(n-13) -1152*a(n-14) -512*a(n-15)
EXAMPLE
Some solutions for n=4
..0..1..1..1. .1..1..0..0. .0..0..1..1. .1..1..1..0. .1..0..0..1
..0..1..1..0. .1..1..1..0. .0..1..1..1. .1..1..0..0. .1..1..1..1
CROSSREFS
Cf. A283784.
Sequence in context: A375521 A316233 A317154 * A267351 A058072 A027304
KEYWORD
nonn
AUTHOR
R. H. Hardin, Mar 16 2017
STATUS
approved