A237309 Number of (n+1)X(1+1) 0..3 arrays with the maximum plus the lower median minus the minimum of every 2X2 subblock equal

256, 1352, 7398, 42474, 246644, 1457838, 8652288, 51729960, 309766574, 1861078542, 11188735904, 67373917686, 405827135812, 2446512539772, 14751429933454, 88985114027282, 536854786667932, 3239769624524494

Offset

1,1

Comments

Column 1 of A237315

Links

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

Formula

Empirical: a(n) = 16*a(n-1) -1222*a(n-3) +4306*a(n-4) +37240*a(n-5) -215317*a(n-6) -540094*a(n-7) +5203112*a(n-8) +2292844*a(n-9) -76124580*a(n-10) +48925344*a(n-11) +731455664*a(n-12) -1009008048*a(n-13) -4767540048*a(n-14) +9634148480*a(n-15) +21068679040*a(n-16) -58279824064*a(n-17) -60171290304*a(n-18) +241589450496*a(n-19) +89789142784*a(n-20) -704484707584*a(n-21) +42074520064*a(n-22) +1448865873408*a(n-23) -538005643264*a(n-24) -2069440729088*a(n-25) +1288382918656*a(n-26) +1977460977664*a(n-27) -1703477510144*a(n-28) -1169175658496*a(n-29) +1362600230912*a(n-30) +349325819904*a(n-31) -643081306112*a(n-32) -6231949312*a(n-33) +161110032384*a(n-34) -21835546624*a(n-35) -16116613120*a(n-36) +3464495104*a(n-37)

Example

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

Crossrefs

Sequence in context: A242257 A206320 A237315 * A188865 A187964 A187956

Adjacent sequences: A237306 A237307 A237308 * A237310 A237311 A237312

Keyword

nonn

Author

R. H. Hardin, Feb 06 2014

Status

approved