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A207440
Number of nX6 0..1 arrays avoiding 0 0 1 and 0 1 0 horizontally and 0 0 1 and 1 0 0 vertically
1
21, 441, 3223, 25689, 243981, 2405923, 24609889, 254583643, 2656816215, 27824719899, 292111495571, 3070203057091, 32292544414703, 339784841081719, 3576079932320067, 37641488144050995, 396241624155306475
OFFSET
1,1
COMMENTS
Column 6 of A207442
LINKS
FORMULA
Empirical: a(n) = 18*a(n-1) +28*a(n-2) -1919*a(n-3) +2979*a(n-4) +95362*a(n-5) -231612*a(n-6) -2949305*a(n-7) +7839332*a(n-8) +63720042*a(n-9) -164002054*a(n-10) -1019649574*a(n-11) +2364255804*a(n-12) +12477359528*a(n-13) -24746209476*a(n-14) -118883561082*a(n-15) +193787167388*a(n-16) +891433774270*a(n-17) -1157423217265*a(n-18) -5297391355794*a(n-19) +5345464441617*a(n-20) +25079478449369*a(n-21) -19313901821721*a(n-22) -95011041062107*a(n-23) +55287876514837*a(n-24) +289144638873935*a(n-25) -127562004651401*a(n-26) -709194571213981*a(n-27) +243339259342592*a(n-28) +1405179088403437*a(n-29) -397217721979316*a(n-30) -2250850677347766*a(n-31) +573775027721393*a(n-32) +2910138635003772*a(n-33) -742562612564521*a(n-34) -3021646123150501*a(n-35) +843533209213982*a(n-36) +2494825273542855*a(n-37) -806746281554019*a(n-38) -1610645232997162*a(n-39) +621348805302137*a(n-40) +791158632247651*a(n-41) -370170752635263*a(n-42) -282576283737423*a(n-43) +163929215752658*a(n-44) +67452204505121*a(n-45) -51463161953584*a(n-46) -8683298468122*a(n-47) +10712887866850*a(n-48) +1992990400*a(n-49) -1326988381076*a(n-50) +156248141136*a(n-51) +79071181632*a(n-52) -15988767360*a(n-53) -1217401920*a(n-54) +347155200*a(n-55) for n>56
EXAMPLE
Some solutions for n=4
..0..1..1..1..1..0....0..1..1..0..1..1....1..0..0..0..0..0....1..1..0..0..0..0
..1..1..1..1..1..1....1..0..1..1..0..1....0..1..1..1..0..1....0..1..1..1..0..0
..0..0..0..0..0..0....0..1..1..0..1..1....1..1..1..0..0..0....1..0..0..0..0..0
..1..1..1..1..1..1....1..0..1..1..0..1....1..0..1..1..0..1....0..1..1..1..0..0
CROSSREFS
Sequence in context: A208167 A207066 A207121 * A188691 A207430 A208372
KEYWORD
nonn
AUTHOR
R. H. Hardin Feb 17 2012
STATUS
approved