A268891 Number of 6Xn binary arrays with some element plus some horizontally or antidiagonally adjacent neighbor totalling two exactly once.

0, 744, 12252, 236960, 3596174, 55491832, 800733668, 11458879568, 159796058742, 2205638713335, 30049236232518, 406011322471540, 5441799029248756, 72482603197808516, 960023683579703110, 12655255863840772464

Offset

1,2

Comments

Row 6 of A268886.

Links

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

Formula

Empirical: a(n) = 2*a(n-1) +237*a(n-2) +556*a(n-3) -17745*a(n-4) -102122*a(n-5) +202421*a(n-6) +2379616*a(n-7) -22987*a(n-8) -27364786*a(n-9) -13031593*a(n-10) +199889692*a(n-11) +91121845*a(n-12) -1012462462*a(n-13) -190133151*a(n-14) +3595273076*a(n-15) -642988498*a(n-16) -8640634728*a(n-17) +4929067410*a(n-18) +12985931924*a(n-19) -13174973746*a(n-20) -9991379232*a(n-21) +18252268246*a(n-22) +272964868*a(n-23) -13058804606*a(n-24) +5323457016*a(n-25) +4041105222*a(n-26) -3401387484*a(n-27) -210272991*a(n-28) +912442186*a(n-29) -169777035*a(n-30) -118543140*a(n-31) +43493135*a(n-32) +6734614*a(n-33) -4652195*a(n-34) -21632*a(n-35) +259061*a(n-36) -13682*a(n-37) -7961*a(n-38) +524*a(n-39) +133*a(n-40) -6*a(n-41) -a(n-42)

Example

Some solutions for n=3
..1..0..0. .0..1..0. .1..0..1. .1..0..1. .1..0..1. .1..0..0. .0..0..1
..0..1..0. .0..0..0. .0..1..0. .1..0..1. .1..0..0. .0..1..0. .1..0..0
..0..0..1. .1..0..1. .0..0..0. .0..0..0. .0..0..1. .0..0..0. .0..1..1
..0..0..1. .1..0..0. .0..0..1. .1..1..0. .1..0..1. .0..1..0. .0..0..1
..1..0..1. .1..1..0. .0..0..0. .0..0..0. .0..0..0. .0..0..0. .0..0..0
..0..1..0. .0..0..1. .0..0..0. .1..0..1. .1..1..0. .0..1..1. .0..0..0

Crossrefs

Cf. A268886.

Sequence in context: A235294 A331674 A235252 * A306281 A210178 A192731

Adjacent sequences: A268888 A268889 A268890 * A268892 A268893 A268894

Keyword

nonn

Author

R. H. Hardin, Feb 15 2016

Status

approved