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A188869
Number of n X 4 binary arrays without the pattern 0 0 0 antidiagonally or horizontally.
1
13, 169, 1901, 21937, 252932, 2915832, 33617513, 387583973, 4468546833, 51518943080, 593974176396, 6848069915941, 78953031067801, 910268322443949, 10494700553747032, 120995905270195676, 1394990644771317341
OFFSET
1,1
COMMENTS
Column 4 of A188874.
LINKS
FORMULA
Empirical: a(n) = 13*a(n-1) -16*a(n-2) -8*a(n-3) -44*a(n-4) +109*a(n-5) -53*a(n-6) +4*a(n-7) for n>8.
Empirical g.f.: x*(13 - 88*x^2 + 32*x^3 + 91*x^4 - 65*x^5 + 17*x^6 - 4*x^7) / (1 - 13*x + 16*x^2 + 8*x^3 + 44*x^4 - 109*x^5 + 53*x^6 - 4*x^7). - Colin Barker, May 01 2018
EXAMPLE
Some solutions for 3 X 4:
..0..0..1..1....0..1..1..1....0..1..0..0....1..1..1..1....1..0..0..1
..1..1..1..0....0..1..1..1....1..0..1..0....0..0..1..1....1..0..1..1
..1..0..0..1....1..0..1..0....1..0..0..1....1..0..1..1....1..1..1..0
CROSSREFS
Cf. A188874.
Sequence in context: A045589 A245228 A093151 * A014956 A171287 A045593
KEYWORD
nonn
AUTHOR
R. H. Hardin, Apr 12 2011
STATUS
approved