A268976 Number of 6Xn 0..2 arrays with some element plus some horizontally or antidiagonally adjacent neighbor totalling two not more than once.

729, 39936, 808704, 16061328, 305242992, 5712070032, 105294777120, 1919046772584, 34636116041280, 620025612531912, 11021514910554528, 194739838779510504, 3422967847878219552, 59892951348957375576

Offset

1,1

Comments

Row 6 of A268971.

Links

R. H. Hardin, Table of n, a(n) for n = 1..210

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

Adjacent sequences: A268973 A268974 A268975 * A268977 A268978 A268979

Keyword

nonn

Author

R. H. Hardin, Feb 16 2016

Status

approved