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A228281
Number of nX6 binary arrays with top left value 1 and no two ones adjacent horizontally, vertically or nw-se diagonally.
2
8, 28, 337, 2448, 21166, 172082, 1428523, 11771298, 97268701, 802886174, 6629901197, 54739811878, 451976078779, 3731849749697, 30812948919061, 254414847888742, 2100639733295629, 17344457600010491, 143208852222784259
OFFSET
1,1
COMMENTS
Column 6 of A228285
LINKS
FORMULA
a(n) = a(n-1) +42*a(n-2) +147*a(n-3) +70*a(n-4) -478*a(n-5) -449*a(n-6) +1199*a(n-7) +732*a(n-8) -2727*a(n-9) +659*a(n-10) +3827*a(n-11) -5776*a(n-12) +3926*a(n-13) -1152*a(n-14) -148*a(n-15) +154*a(n-16) +32*a(n-17) -29*a(n-18) -6*a(n-19) +3*a(n-20) +a(n-21)
EXAMPLE
Some solutions for n=4
..1..0..0..0..0..0....1..0..0..0..1..0....1..0..0..0..1..0....1..0..1..0..0..1
..0..0..0..1..0..0....0..0..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..0..0..0....0..0..1..0..0..1....0..0..0..0..0..0
..0..0..0..0..1..0....0..0..0..1..0..1....0..0..0..0..0..0....0..0..0..1..0..0
CROSSREFS
See A228277-A228285, especially the latter.
Sequence in context: A230702 A374280 A244613 * A146977 A374138 A068623
KEYWORD
nonn
AUTHOR
R. H. Hardin Aug 19 2013
EXTENSIONS
Edited by N. J. A. Sloane, Aug 22 2013
STATUS
approved