

A228681


Number of n X 6 binary arrays with no two ones adjacent horizontally, diagonally or antidiagonally.


1



21, 217, 2529, 28977, 333517, 3837761, 44171841, 508425617, 5852202757, 67361890809, 775372578689, 8924976046401, 102731553583965, 1182498825731233, 13611237290882689, 156673123529460833, 1803397245448244085
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OFFSET

1,1


LINKS

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


FORMULA

Empirical: a(n) = 14*a(n1)  17*a(n2)  142*a(n3) + 59*a(n4) + 352*a(n5) + 103*a(n6)  48*a(n7).
Empirical g.f.: x*(21  77*x  152*x^2 + 242*x^3 + 407*x^4 + 55*x^5  48*x^6) / (1  14*x + 17*x^2 + 142*x^3  59*x^4  352*x^5  103*x^6 + 48*x^7).  Colin Barker, Sep 12 2018


EXAMPLE

Some solutions for n=4:
..0..0..0..0..0..0....0..0..0..1..0..0....0..0..0..1..0..0....1..0..1..0..1..0
..1..0..0..1..0..0....0..1..0..1..0..1....0..0..0..0..0..1....0..0..0..0..0..0
..0..0..0..0..0..1....0..0..0..0..0..1....1..0..0..0..0..0....1..0..1..0..0..0
..1..0..0..0..0..0....0..0..0..0..0..1....0..0..1..0..1..0....1..0..0..0..1..0


CROSSREFS

Column 6 of A228683.
Sequence in context: A053063 A060933 A075282 * A165223 A152161 A008421
Adjacent sequences: A228678 A228679 A228680 * A228682 A228683 A228684


KEYWORD

nonn


AUTHOR

R. H. Hardin, Aug 30 2013


STATUS

approved



