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

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

R. H. Hardin, Table of n, a(n) for n = 1..210

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

Adjacent sequences: A203918 A203919 A203920 * A203922 A203923 A203924

Keyword

nonn

Author

R. H. Hardin Jan 07 2012

Status

approved