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A203921
Number of (n+2)X8 0..1 arrays with every 3X3 subblock having equal diagonal elements or equal antidiagonal elements, and new values 0..1 introduced in row major order
1
63368, 279752, 949442, 3220722, 11082632, 38438912, 132454088, 457591752, 1580456642, 5462842338, 18857985218, 65068116768, 224346831858, 774243280962, 2671160165858, 9217053951008, 31798924865138, 109735890288200
OFFSET
1,1
COMMENTS
Column 6 of A203923
LINKS
FORMULA
Empirical: a(n) = 2*a(n-1) +4*a(n-2) +21*a(n-4) -44*a(n-5) +77*a(n-6) -330*a(n-7) +725*a(n-8) +1075*a(n-9) -272*a(n-10) -7437*a(n-11) +3981*a(n-12) -38316*a(n-13) +9844*a(n-14) -175345*a(n-15) -305724*a(n-16) +136192*a(n-17) +819037*a(n-18) -223626*a(n-19) +2830879*a(n-20) +708245*a(n-21) +14405913*a(n-22) +16441846*a(n-23) -4553163*a(n-24) -1990010*a(n-25) -1691368*a(n-26) -128021433*a(n-27) -18648377*a(n-28) -474112544*a(n-29) -502121032*a(n-30) -12957696*a(n-31) -42783040*a(n-32) +223768064*a(n-33) +127220736*a(n-34) +160456704*a(n-35) +10553180160*a(n-36) +6607732736*a(n-37) -3974365184*a(n-38) +25952256*a(n-39) -3029598208*a(n-40) -1849688064*a(n-41) -1717567488*a(n-42) -1761607680*a(n-43) -1744830464*a(n-44) +1073741824*a(n-45) for n>48
EXAMPLE
Some solutions for n=3
..0..0..1..1..1..1..1..1....0..0..1..1..1..0..1..0....0..0..1..1..1..0..1..0
..1..0..0..1..1..1..1..0....0..0..0..1..0..1..0..0....1..1..1..1..0..1..0..1
..1..0..0..0..1..1..1..0....1..0..0..0..1..0..1..1....1..1..1..0..1..0..1..0
..0..0..0..0..0..1..1..1....0..1..0..0..0..1..1..1....1..1..0..1..0..1..0..0
..0..0..1..0..0..0..1..1....1..0..1..0..0..1..1..0....1..0..0..0..1..0..0..0
CROSSREFS
Sequence in context: A209793 A115748 A226003 * A237918 A294147 A242142
KEYWORD
nonn
AUTHOR
R. H. Hardin Jan 07 2012
STATUS
approved