A269074 Number of nX7 binary arrays with some element plus some horizontally, diagonally or antidiagonally adjacent neighbor totalling two not more than once.

72, 1204, 27042, 542112, 10778640, 210476400, 4064720816, 77785162880, 1477636398784, 27897108860960, 523921783242624, 9794822341611072, 182387895832407680, 3384281324193062016, 62600172035227164032

Offset

1,1

Comments

Column 7 of A269075.

Links

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

Formula

Empirical: a(n) = 60*a(n-1) -1352*a(n-2) +13344*a(n-3) -35948*a(n-4) -311480*a(n-5) +1985472*a(n-6) +1821840*a(n-7) -31021776*a(n-8) +4125984*a(n-9) +251967152*a(n-10) -46853056*a(n-11) -1173410880*a(n-12) -138650624*a(n-13) +2912101888*a(n-14) +1295316992*a(n-15) -3360870400*a(n-16) -2339016704*a(n-17) +1368141824*a(n-18) +1168457728*a(n-19) -291553280*a(n-20) -245170176*a(n-21) +45023232*a(n-22) +19922944*a(n-23) -4194304*a(n-24) for n>25

Example

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

Crossrefs

Cf. A269075.

Sequence in context: A269088 A168194 A249713 * A200556 A239423 A128800

Adjacent sequences: A269071 A269072 A269073 * A269075 A269076 A269077

Keyword

nonn

Author

R. H. Hardin, Feb 19 2016

Status

approved