A237678 Number of (n+1)X(1+1) 0..2 arrays colored with the upper median plus the lower median minus the minimum of every 2X2 subblock

81, 474, 2741, 15948, 93093, 541880, 3152844, 18356756, 106893088, 622285828, 3622715432, 21091482008, 122794559800, 714891615808, 4162016007648, 24230928689312, 141070302809152, 821296712783104, 4781509809549568

Offset

1,1

Comments

Column 1 of A237683

Links

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

Formula

Empirical: a(n) = 72*a(n-3) +456*a(n-4) +1084*a(n-5) +3312*a(n-6) +712*a(n-7) -9384*a(n-8) -26848*a(n-9) -73104*a(n-10) +19232*a(n-11) +112256*a(n-12) +249216*a(n-13) +378368*a(n-14) -641536*a(n-15) -627712*a(n-16) +231424*a(n-17) +372736*a(n-18)

Example

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

Crossrefs

Sequence in context: A237683 A236640 A236780 * A236635 A236775 A205293

Adjacent sequences: A237675 A237676 A237677 * A237679 A237680 A237681

Keyword

nonn

Author

R. H. Hardin, Feb 11 2014

Status

approved