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A251216
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Number of (n+1)X(5+1) 0..1 arrays with no 2X2 subblock having zero or two 1s
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1
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269, 1807, 12503, 91777, 666522, 4907873, 35978029, 264753513, 1945208633, 14308155872, 105188553635, 773584601045, 5688101213179, 41828997394195, 307581228052004, 2261827178919767, 16632180381484013, 122305218359499415
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OFFSET
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1,1
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COMMENTS
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LINKS
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FORMULA
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Empirical: a(n) = 4*a(n-1) +82*a(n-2) -251*a(n-3) -2703*a(n-4) +6901*a(n-5) +48780*a(n-6) -108989*a(n-7) -546663*a(n-8) +1098266*a(n-9) +4063202*a(n-10) -7456259*a(n-11) -20776941*a(n-12) +35171846*a(n-13) +74472363*a(n-14) -117177514*a(n-15) -188172530*a(n-16) +277316513*a(n-17) +333213184*a(n-18) -464708588*a(n-19) -406101104*a(n-20) +544837887*a(n-21) +329069381*a(n-22) -437315394*a(n-23) -166173070*a(n-24) +231940192*a(n-25) +44995064*a(n-26) -76531088*a(n-27) -3116992*a(n-28) +13999072*a(n-29) -1163072*a(n-30) -1066176*a(n-31) +191232*a(n-32)
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EXAMPLE
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Some solutions for n=4
..1..1..1..1..1..1....0..1..1..0..1..1....1..0..0..1..1..1....0..1..0..1..1..0
..1..1..0..1..1..1....1..1..1..1..1..0....1..1..0..0..1..0....1..1..1..1..1..1
..0..1..1..1..1..0....1..0..1..1..0..0....1..0..0..1..1..1....1..1..1..1..1..0
..1..1..1..1..1..1....1..1..1..0..0..1....0..0..1..1..1..1....0..1..0..1..1..1
..1..1..0..1..1..0....1..0..1..1..0..0....0..1..1..0..1..0....0..0..0..0..1..1
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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STATUS
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approved
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