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A318341
Number of nX6 0..1 arrays with every element unequal to 0, 1, 2 or 6 horizontally, vertically or antidiagonally adjacent elements, with upper left element zero.
1
32, 89, 160, 343, 1115, 4133, 16267, 66070, 270320, 1112195, 4584060, 18912384, 78063418, 322286580, 1330722690, 5494862763, 22690219542, 93697259411, 386917457753, 1597759628888, 6597895365718, 27245818039527, 112510877313046
OFFSET
1,1
COMMENTS
Column 6 of A318343.
LINKS
FORMULA
Empirical: a(n) = 4*a(n-1) +9*a(n-2) -28*a(n-3) -57*a(n-4) +78*a(n-5) +199*a(n-6) -73*a(n-7) -366*a(n-8) -89*a(n-9) +336*a(n-10) +298*a(n-11) -42*a(n-12) -362*a(n-13) -234*a(n-14) +215*a(n-15) +227*a(n-16) +16*a(n-17) -99*a(n-18) -65*a(n-19) +7*a(n-20) +27*a(n-21) +4*a(n-22) -4*a(n-23) for n>27
EXAMPLE
Some solutions for n=5
..0..1..1..1..0..0. .0..1..1..1..1..1. .0..1..1..1..1..1. .0..0..0..0..0..0
..0..1..1..1..0..0. .1..1..1..1..1..1. .1..0..1..0..1..1. .0..0..1..0..0..0
..0..1..1..1..0..0. .1..1..1..1..1..1. .1..1..1..1..1..1. .0..0..0..0..0..0
..0..1..1..1..0..0. .1..0..1..1..0..1. .1..1..1..0..1..1. .0..0..0..0..0..0
..0..1..1..1..0..0. .1..1..1..1..1..1. .1..1..1..1..1..0. .0..0..0..0..0..1
CROSSREFS
Cf. A318343.
Sequence in context: A184029 A184021 A317762 * A318073 A279713 A228801
KEYWORD
nonn
AUTHOR
R. H. Hardin, Aug 24 2018
STATUS
approved