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A251501
Number of (n+1)X(2+1) 0..3 arrays with every 2X2 subblock summing to 3 4 5 6 7 8 or 9
1
3250, 170038, 8888108, 464687066, 24294592462, 1270162626436, 66406260528122, 3471832190942254, 181513288991552436, 9489823318679339926, 496144095673713305306, 25939256760196067292272, 1356148439815055707788150
OFFSET
1,1
COMMENTS
Column 2 of A251507
LINKS
FORMULA
Empirical: a(n) = 51*a(n-1) +98*a(n-2) -1591*a(n-3) -1723*a(n-4) +10123*a(n-5) +2357*a(n-6) -17329*a(n-7) +4004*a(n-8) +5484*a(n-9) -1920*a(n-10)
EXAMPLE
Some solutions for n=2
..2..1..1....1..0..0....0..2..2....1..0..3....2..2..0....1..0..0....3..2..0
..3..2..2....2..2..2....2..1..1....2..3..0....1..3..0....2..2..1....0..2..2
..0..3..0....0..0..3....0..0..2....1..3..3....0..1..2....2..1..0....1..3..1
CROSSREFS
Sequence in context: A238254 A187135 A185840 * A106722 A031555 A106723
KEYWORD
nonn
AUTHOR
R. H. Hardin, Dec 03 2014
STATUS
approved