A237000 Number of (n+1)X(1+1) 0..3 arrays with the upper median plus the lower median of every 2X2 subblock equal

256, 1200, 5288, 26320, 131280, 677344, 3518120, 18477584, 97461616, 516386016, 2742670088, 14598685968, 77817078928, 415298087392, 2218380038504, 11858851965712, 63433486272944, 339491529596384, 1817787857754056

Offset

1,1

Comments

Column 1 of A237007

Links

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

Formula

Empirical: a(n) = 13*a(n-1) -21*a(n-2) -329*a(n-3) +1031*a(n-4) +3487*a(n-5) -13091*a(n-6) -21599*a(n-7) +79282*a(n-8) +90220*a(n-9) -248320*a(n-10) -246896*a(n-11) +371200*a(n-12) +361344*a(n-13) -192000*a(n-14) -184320*a(n-15)

Example

Some solutions for n=5
..2..2....1..2....1..3....1..3....0..1....0..3....2..0....2..1....2..3....0..3
..3..1....1..2....2..1....0..3....2..1....1..3....2..1....2..1....2..2....2..1
..3..0....1..3....2..1....1..3....0..1....3..1....2..1....1..2....2..1....0..2
..2..2....2..1....1..3....1..3....1..2....2..2....3..1....2..0....2..2....2..1
..2..2....2..1....2..0....2..2....1..0....2..2....2..1....1..3....3..0....2..1
..3..1....2..1....2..1....2..1....3..1....1..3....1..3....2..0....3..1....2..0

Crossrefs

Sequence in context: A237211 A237204 A237007 * A236979 A236973 A237956

Adjacent sequences: A236997 A236998 A236999 * A237001 A237002 A237003

Keyword

nonn

Author

R. H. Hardin, Feb 02 2014

Status

approved