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A317738
Number of nX5 0..1 arrays with every element unequal to 2 or 3 horizontally, vertically or antidiagonally adjacent elements, with upper left element zero.
1
0, 4, 2, 14, 14, 38, 74, 149, 269, 662, 1294, 2721, 5911, 12084, 25175, 53473, 111383, 233690, 490578, 1030868, 2158490, 4533365, 9504248, 19950172, 41823355, 87810137, 184117052, 386450223, 810444428, 1700925286, 3567310635, 7486285033
OFFSET
1,2
COMMENTS
Column 5 of A317741.
LINKS
FORMULA
Empirical: a(n) = 2*a(n-2) +5*a(n-3) +5*a(n-4) -6*a(n-5) -a(n-6) -15*a(n-7) +16*a(n-8) -23*a(n-9) +4*a(n-10) -82*a(n-11) -46*a(n-12) -44*a(n-13) +101*a(n-14) +160*a(n-15) +83*a(n-16) +21*a(n-17) -52*a(n-18) +83*a(n-19) +154*a(n-20) +284*a(n-21) +155*a(n-22) -76*a(n-23) -161*a(n-24) -125*a(n-25) -49*a(n-26) -3*a(n-27) +40*a(n-28) +11*a(n-29) -5*a(n-30) -2*a(n-31) -2*a(n-32) +a(n-33) for n>39
EXAMPLE
Some solutions for n=5
..0..1..0..0..1. .0..1..0..1..0. .0..1..0..1..0. .0..1..0..0..0
..1..1..1..0..0. .1..0..0..1..0. .1..0..0..1..1. .1..1..1..1..1
..0..1..1..0..1. .0..0..1..1..0. .1..0..0..1..0. .0..1..1..0..0
..0..1..0..0..1. .1..1..1..1..1. .1..0..1..1..0. .0..1..0..0..1
..0..1..0..1..0. .0..0..0..1..0. .1..0..1..0..1. .1..0..1..1..0
CROSSREFS
Cf. A317741.
Sequence in context: A248249 A161134 A184183 * A224893 A087957 A360084
KEYWORD
nonn
AUTHOR
R. H. Hardin, Aug 05 2018
STATUS
approved