A236491 Number of (2+1)X(n+1) 0..2 arrays with the difference between each 2X2 subblock maximum and minimum lexicographically nondecreasing columnwise and nonincreasing rowwise.

583, 9839, 156087, 2339313, 34149421, 489696691, 6952708569, 98111759309, 1379571183553, 19357628896563, 271287317021009, 3799259763055641, 53185320056350705, 744360921433456291, 10416408405407546263

Offset

1,1

Comments

Row 2 of A236490

Links

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

Formula

Empirical: a(n) = 26*a(n-1) -112*a(n-2) -1715*a(n-3) +11594*a(n-4) +50442*a(n-5) -400232*a(n-6) -874284*a(n-7) +7189922*a(n-8) +9011756*a(n-9) -78274368*a(n-10) -51795422*a(n-11) +552465656*a(n-12) +120595776*a(n-13) -2596861844*a(n-14) +326924536*a(n-15) +8183202175*a(n-16) -3189752134*a(n-17) -17284950088*a(n-18) +10235206809*a(n-19) +24454223558*a(n-20) -18527589410*a(n-21) -22947355964*a(n-22) +20982286124*a(n-23) +13811550904*a(n-24) -15262048328*a(n-25) -4856880496*a(n-26) +7034342560*a(n-27) +699317696*a(n-28) -1944381056*a(n-29) +96473344*a(n-30) +283617792*a(n-31) -43029504*a(n-32) -15593472*a(n-33) +3317760*a(n-34)

Example

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

Crossrefs

Sequence in context: A396137 A032373 A236486 * A235433 A205069 A187050

Adjacent sequences: A236488 A236489 A236490 * A236492 A236493 A236494

Keyword

nonn

Author

R. H. Hardin, Jan 27 2014

Status

approved