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A318093 Number of nX3 0..1 arrays with every element unequal to 1, 2, 3 or 5 horizontally, vertically or antidiagonally adjacent elements, with upper left element zero. 1
1, 16, 45, 220, 795, 3310, 12774, 51298, 201637, 802119, 3169137, 12571062, 49748730, 197152806, 780649100, 3092658411, 12248195877, 48517164179, 192162096401, 761151962411, 3014780751286, 11941310147017, 47297795017905 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,2
COMMENTS
Column 3 of A318098.
LINKS
FORMULA
Empirical: a(n) = 14*a(n-2) +18*a(n-3) -23*a(n-4) -69*a(n-5) -69*a(n-6) -38*a(n-7) +82*a(n-8) +261*a(n-9) +101*a(n-10) -10*a(n-11) -20*a(n-12) -112*a(n-13) -112*a(n-14) -90*a(n-15) -24*a(n-16) -12*a(n-17) +4*a(n-18) +4*a(n-19) for n>21
EXAMPLE
Some solutions for n=5
..0..1..1. .0..1..1. .0..1..0. .0..0..1. .0..0..1. .0..1..1. .0..0..1
..0..0..1. .0..0..0. .1..1..1. .1..1..0. .1..1..0. .1..0..0. .1..1..0
..1..1..1. .0..1..0. .0..1..1. .1..0..1. .1..0..1. .1..1..1. .1..1..0
..0..0..0. .0..1..1. .0..0..0. .1..1..1. .1..1..0. .1..1..0. .0..1..1
..0..1..1. .1..1..0. .1..0..1. .0..0..0. .1..0..1. .0..0..1. .0..1..0
CROSSREFS
Cf. A318098.
Sequence in context: A209993 A322343 A345754 * A223029 A244343 A235772
KEYWORD
nonn
AUTHOR
R. H. Hardin, Aug 16 2018
STATUS
approved

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Last modified February 28 18:11 EST 2024. Contains 370400 sequences. (Running on oeis4.)