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A188749
Number of 4 X n binary arrays without the pattern 1 1 1 diagonally, vertically or antidiagonally.
1
13, 169, 1651, 17286, 184411, 1944586, 20544154, 217243096, 2296414963, 24275369558, 256625412014, 2712870938389, 28678635692942, 303171638077403, 3204930092906176, 33880400190604953, 358161194075528039
OFFSET
1,1
COMMENTS
Row 4 of A188747.
LINKS
FORMULA
Empirical: a(n) = 11*a(n-1) +2*a(n-2) -27*a(n-3) -420*a(n-4) -568*a(n-5) +3095*a(n-6) +2148*a(n-7) -2947*a(n-8) -4914*a(n-9) -3147*a(n-10) +1801*a(n-11) +4012*a(n-12) +2286*a(n-13) -228*a(n-14) -396*a(n-15) -656*a(n-16) -288*a(n-17) +192*a(n-18).
EXAMPLE
Some solutions for 4 X 3
..1..0..1....0..1..1....1..0..1....0..0..1....1..1..0....0..0..0....0..1..0
..0..1..0....0..0..0....1..1..1....0..0..1....1..0..1....0..0..0....0..0..0
..0..1..0....0..1..0....0..1..0....1..0..0....0..0..0....1..0..1....1..1..1
..0..0..1....0..0..0....0..0..0....1..0..1....0..0..0....0..1..0....1..0..1
CROSSREFS
Cf. A188747.
Sequence in context: A188562 A207084 A207178 * A045589 A245228 A093151
KEYWORD
nonn
AUTHOR
R. H. Hardin, Apr 09 2011
STATUS
approved