A237922 Number of (n+1)X(1+1) 0..3 arrays with the maximum plus the lower median of every 2X2 subblock differing from its horizontal and vertical neighbors by exactly one

256, 1632, 10316, 66512, 431640, 2776536, 17920936, 115383848, 745952272, 4801239096, 31023158644, 199699207808, 1290589180896, 8307345571648, 53684274618860, 345562572268528, 2233164262251368, 14374690362585720

Offset

1,1

Comments

Column 1 of A237927

Links

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

Formula

Empirical: a(n) = 1181*a(n-4) +22032*a(n-6) +73432*a(n-8) -1336476*a(n-10) -12277371*a(n-12) -12126056*a(n-14) +265052455*a(n-16) +1326988676*a(n-18) +2166031440*a(n-20) -838485120*a(n-22) -6967321344*a(n-24) -7539800064*a(n-26) -1875689472*a(n-28) +700055552*a(n-30)

Example

Some solutions for n=4
..1..1....1..2....2..2....3..3....0..0....1..3....1..2....2..0....2..0....0..3
..2..3....1..1....1..0....1..1....0..2....0..3....1..2....2..3....0..0....3..1
..2..1....1..0....2..3....1..2....1..1....0..2....3..0....1..1....3..3....2..2
..1..3....1..2....0..0....1..3....0..3....1..0....2..0....0..2....1..0....1..2
..2..2....2..2....2..2....2..2....1..0....2..2....0..2....2..0....1..2....1..2

Crossrefs

Sequence in context: A238155 A238148 A237927 * A238072 A238065 A237538

Adjacent sequences: A237919 A237920 A237921 * A237923 A237924 A237925

Keyword

nonn

Author

R. H. Hardin, Feb 15 2014

Status

approved