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A268891 Number of 6Xn binary arrays with some element plus some horizontally or antidiagonally adjacent neighbor totalling two exactly once. 1
0, 744, 12252, 236960, 3596174, 55491832, 800733668, 11458879568, 159796058742, 2205638713335, 30049236232518, 406011322471540, 5441799029248756, 72482603197808516, 960023683579703110, 12655255863840772464 (list; graph; refs; listen; history; text; internal format)
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

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Last modified July 26 10:21 EDT 2021. Contains 346294 sequences. (Running on oeis4.)