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A268780
Number of n X 7 binary arrays with some element plus some horizontally, vertically, diagonally or antidiagonally adjacent neighbor totalling two no more than once.
1
72, 766, 10615, 115391, 1288693, 13493468, 140404442, 1425678976, 14341399141, 142487073304, 1404716302427, 13742060955231, 133640514636584, 1292631496259982, 12446235637750465, 119353876258739189
OFFSET
1,1
COMMENTS
Column 7 of A268781.
LINKS
FORMULA
Empirical: a(n) = 12*a(n-1) +64*a(n-2) -942*a(n-3) -1476*a(n-4) +26868*a(n-5) +2249*a(n-6) -376788*a(n-7) +333472*a(n-8) +2686292*a(n-9) -4376424*a(n-10) -8985248*a(n-11) +21881197*a(n-12) +12658940*a(n-13) -55768960*a(n-14) +923990*a(n-15) +80699088*a(n-16) -25850884*a(n-17) -69171189*a(n-18) +34934900*a(n-19) +34833816*a(n-20) -22502076*a(n-21) -9502460*a(n-22) +7752808*a(n-23) +1023260*a(n-24) -1356480*a(n-25) +55136*a(n-26) +94080*a(n-27) -14400*a(n-28).
EXAMPLE
Some solutions for n=4
..0..0..0..0..1..0..0. .0..1..0..0..0..0..0. .1..0..1..0..0..1..0
..0..0..0..0..0..0..0. .0..0..0..1..0..1..0. .0..0..0..0..0..0..1
..0..0..0..0..1..0..0. .0..0..0..0..0..0..0. .1..0..0..0..0..0..0
..0..0..0..1..0..0..0. .1..0..0..0..0..0..1. .0..0..0..0..0..0..1
CROSSREFS
Cf. A268781.
Sequence in context: A008448 A282213 A304828 * A086579 A113855 A082949
KEYWORD
nonn
AUTHOR
R. H. Hardin, Feb 13 2016
STATUS
approved