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A231658
Number of nX3 0..2 arrays with no element less than a strict majority of its horizontal, vertical and antidiagonal neighbors
1
9, 93, 1197, 13434, 144465, 1607589, 17962078, 199451319, 2215334132, 24630393761, 273787728195, 3042987314978, 33822943262208, 375948173660383, 4178682035747595, 46446248901585653, 516253337817244309
OFFSET
1,1
COMMENTS
Column 3 of A231663
LINKS
FORMULA
Empirical: a(n) = 22*a(n-1) -187*a(n-2) +1087*a(n-3) -5320*a(n-4) +19314*a(n-5) -48040*a(n-6) +59172*a(n-7) +63954*a(n-8) -540406*a(n-9) +1405698*a(n-10) -3249182*a(n-11) +6903927*a(n-12) -2526040*a(n-13) -10496366*a(n-14) -2177417*a(n-15) +34815192*a(n-16) -61109845*a(n-17) +118442561*a(n-18) -1919557*a(n-19) -412868015*a(n-20) +741502962*a(n-21) -1238756535*a(n-22) +1796964457*a(n-23) -1329779415*a(n-24) +260960844*a(n-25) +531253784*a(n-26) -1824042081*a(n-27) +3351472259*a(n-28) -2252500439*a(n-29) +1457224992*a(n-30) -937992344*a(n-31) -796856097*a(n-32) +1654523544*a(n-33) -1270928793*a(n-34) +779543513*a(n-35) -885493704*a(n-36) +346377936*a(n-37) +423931249*a(n-38) -101753248*a(n-39) +87239521*a(n-40) -277055497*a(n-41) +214365724*a(n-42) +93299496*a(n-43) -100406405*a(n-44) -66979600*a(n-45) -442294*a(n-46) +43755691*a(n-47) -14512622*a(n-48) -17608691*a(n-49) +4308011*a(n-50) +5162569*a(n-51) +1374874*a(n-52) -853220*a(n-53) -293040*a(n-54) +48896*a(n-55) -5280*a(n-56) -2304*a(n-57)
EXAMPLE
Some solutions for n=5
..0..0..0....0..0..2....0..0..2....0..0..0....0..2..2....0..0..1....1..0..0
..1..1..0....0..0..0....2..0..0....1..1..0....0..0..0....0..2..1....0..0..2
..1..0..0....2..0..0....2..0..1....1..0..0....0..2..0....1..1..2....1..0..1
..1..0..0....1..0..0....2..0..2....0..0..0....2..0..0....1..1..1....0..0..1
..2..1..1....1..1..2....0..0..0....2..1..0....2..0..0....2..2..1....2..0..0
CROSSREFS
Sequence in context: A261688 A246212 A163951 * A034992 A048359 A307961
KEYWORD
nonn
AUTHOR
R. H. Hardin, Nov 12 2013
STATUS
approved