A235749 Number of (n+1)X(1+1) 0..3 arrays with the sum of each 2X2 subblock two median terms lexicographically nondecreasing columnwise and nonincreasing rowwise

256, 2648, 26852, 231182, 1922672, 14817810, 110573053, 791130664, 5516314404, 37453877908, 249324764892, 1629332300710, 10488074069468, 66598005286126, 417974386184201, 2595931749382104, 15974904340482264, 97498090630154000

Offset

1,1

Comments

Column 1 of A235752

Links

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

Formula

Empirical: a(n) = 16*a(n-1) -3*a(n-2) -1116*a(n-3) +3195*a(n-4) +36776*a(n-5) -144355*a(n-6) -775876*a(n-7) +3409369*a(n-8) +11994752*a(n-9) -52035329*a(n-10) -145821540*a(n-11) +551539761*a(n-12) +1428073416*a(n-13) -4145223065*a(n-14) -11151370108*a(n-15) +21729158076*a(n-16) +67484344064*a(n-17) -73656117248*a(n-18) -305148542976*a(n-19) +117869487680*a(n-20) +984593256704*a(n-21) +184038815744*a(n-22) -2112780488704*a(n-23) -1459803293696*a(n-24) +2607031529472*a(n-25) +3342204194816*a(n-26) -1030546145280*a(n-27) -3447562665984*a(n-28) -1135057305600*a(n-29) +1114979696640*a(n-30) +934281216000*a(n-31) +203843174400*a(n-32)

Example

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

Crossrefs

Sequence in context: A236501 A235752 A235815 * A236596 A236593 A236319

Adjacent sequences: A235746 A235747 A235748 * A235750 A235751 A235752

Keyword

nonn

Author

R. H. Hardin, Jan 15 2014

Status

approved