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A207708
Number of 7Xn 0..1 arrays avoiding 0 0 0 and 0 1 0 horizontally and 0 0 1 and 1 1 0 vertically
1
14, 196, 966, 4761, 32775, 225625, 1369900, 8317456, 52895444, 336392281, 2102483853, 13140724689, 82666212354, 520040015044, 3263532374278, 20480430831961, 128643137927197, 808042422131569, 5073797510995256
OFFSET
1,1
COMMENTS
Row 7 of A207703
LINKS
FORMULA
Empirical: a(n) = 4*a(n-1) +57*a(n-3) +284*a(n-4) -314*a(n-5) -39*a(n-6) -4155*a(n-7) -16616*a(n-8) +6874*a(n-9) -2657*a(n-10) +97060*a(n-11) +359797*a(n-12) -66778*a(n-13) +77045*a(n-14) -1019094*a(n-15) -3617126*a(n-16) +385281*a(n-17) -504943*a(n-18) +5451396*a(n-19) +18594594*a(n-20) -1422920*a(n-21) +811498*a(n-22) -15736153*a(n-23) -51158769*a(n-24) +2752369*a(n-25) +516925*a(n-26) +25909668*a(n-27) +79811349*a(n-28) -2261639*a(n-29) -2183637*a(n-30) -25220973*a(n-31) -74042440*a(n-32) +178375*a(n-33) +1988830*a(n-34) +14786834*a(n-35) +42245216*a(n-36) +785427*a(n-37) -907260*a(n-38) -5336110*a(n-39) -15218216*a(n-40) -507838*a(n-41) +243745*a(n-42) +1199159*a(n-43) +3512433*a(n-44) +149316*a(n-45) -40022*a(n-46) -166404*a(n-47) -519313*a(n-48) -24231*a(n-49) +3857*a(n-50) +13706*a(n-51) +48268*a(n-52) +2210*a(n-53) -196*a(n-54) -607*a(n-55) -2690*a(n-56) -105*a(n-57) +4*a(n-58) +11*a(n-59) +81*a(n-60) +2*a(n-61) -a(n-64)
EXAMPLE
Some solutions for n=4
..0..1..1..1....1..1..1..0....0..0..1..1....0..0..1..1....1..1..0..0
..0..1..1..0....0..1..1..0....1..1..1..0....1..0..1..1....1..1..1..1
..0..1..1..0....0..1..1..0....0..1..1..0....0..0..1..1....1..1..1..1
..0..1..1..0....0..1..1..0....1..1..1..0....0..0..1..1....1..1..1..1
..0..1..1..0....0..1..1..0....1..1..1..0....0..0..1..1....1..1..1..1
..0..1..1..0....0..1..1..0....1..1..1..0....0..0..1..1....1..1..1..1
..0..1..1..0....0..1..1..0....1..1..1..0....0..0..1..1....1..1..1..1
CROSSREFS
Sequence in context: A209654 A207074 A207407 * A207253 A208291 A207439
KEYWORD
nonn
AUTHOR
R. H. Hardin Feb 19 2012
STATUS
approved