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A268976
Number of 6Xn 0..2 arrays with some element plus some horizontally or antidiagonally adjacent neighbor totalling two not more than once.
1
729, 39936, 808704, 16061328, 305242992, 5712070032, 105294777120, 1919046772584, 34636116041280, 620025612531912, 11021514910554528, 194739838779510504, 3422967847878219552, 59892951348957375576
OFFSET
1,1
COMMENTS
Row 6 of A268971.
LINKS
FORMULA
Empirical: a(n) = 60*a(n-1) -1466*a(n-2) +19056*a(n-3) -143515*a(n-4) +608478*a(n-5) -957350*a(n-6) -3924114*a(n-7) +27201539*a(n-8) -68079378*a(n-9) +46537423*a(n-10) +212613240*a(n-11) -785654632*a(n-12) +1389943104*a(n-13) -1544105168*a(n-14) +1125401088*a(n-15) -524553472*a(n-16) +142135296*a(n-17) -17040384*a(n-18) for n>26
EXAMPLE
Some solutions for n=2
..2..1. .2..2. .0..1. .1..1. .0..0. .2..2. .2..0. .0..1. .0..0. .2..2
..2..1. .1..2. .2..1. .2..1. .1..0. .1..0. .0..1. .0..0. .0..1. .2..1
..0..0. .2..1. .2..1. .0..1. .0..1. .0..1. .2..2. .1..0. .2..0. .0..1
..1..2. .1..2. .2..2. .0..1. .1..0. .0..1. .1..0. .1..0. .1..0. .0..0
..1..1. .2..1. .0..1. .2..2. .0..0. .2..1. .1..2. .1..0. .0..0. .0..0
..0..0. .0..1. .0..1. .1..0. .1..0. .2..1. .1..2. .0..1. .1..2. .1..0
CROSSREFS
Cf. A268971.
Sequence in context: A203651 A036536 A223281 * A224357 A016770 A224016
KEYWORD
nonn
AUTHOR
R. H. Hardin, Feb 16 2016
STATUS
approved