A237931 Number of (n+1)X(1+1) 0..3 arrays with the upper median plus the lower median minus the minimum of every 2X2 subblock differing from its horizontal and vertical neighbors by exactly one

256, 1718, 11701, 81402, 563166, 3880918, 26804881, 185489824, 1282099556, 8852862392, 61169759404, 422870170848, 2922385929712, 20190059774152, 139517455447976, 964213093638072, 6663225933024004, 46041769193957056

Offset

1,1

Comments

Column 1 of A237936

Links

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

Formula

Empirical: a(n) = 1888*a(n-4) +26908*a(n-6) -301104*a(n-8) -4523964*a(n-10) +9356144*a(n-12) +158092496*a(n-14) +15024960*a(n-16) -2150807552*a(n-18) -1973442560*a(n-20) +11283515392*a(n-22) +13873016832*a(n-24) -19456245760*a(n-26) -21131821056*a(n-28) +10415243264*a(n-30) +385875968*a(n-32) -96468992*a(n-34) -16777216*a(n-36)

Example

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

Crossrefs

Sequence in context: A237175 A237169 A237936 * A237494 A237489 A238054

Adjacent sequences: A237928 A237929 A237930 * A237932 A237933 A237934

Keyword

nonn

Author

R. H. Hardin, Feb 16 2014

Status

approved