A236812 Number of (n+1)X(1+1) 0..2 arrays with the maximum plus the lower median minus the minimum of every 2X2 subblock equal

81, 303, 1162, 4627, 18527, 75330, 307321, 1264403, 5216986, 21640527, 89986987, 375549402, 1570552173, 6585201767, 27658875370, 116397378211, 490534291751, 2070328353634, 8748087545329, 37007121293131, 156698572216250

Offset

1,1

Comments

Column 1 of A236819

Links

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

Formula

Empirical: a(n) = 9*a(n-1) -2*a(n-2) -181*a(n-3) +349*a(n-4) +1204*a(n-5) -3474*a(n-6) -2856*a(n-7) +13672*a(n-8) -432*a(n-9) -24464*a(n-10) +10352*a(n-11) +18944*a(n-12) -11968*a(n-13) -4736*a(n-14) +3584*a(n-15)

Example

Some solutions for n=5
..1..0....0..1....2..1....1..0....2..2....1..0....0..2....2..0....2..2....0..1
..2..0....2..0....0..0....0..2....2..2....2..0....0..0....1..1....2..1....2..1
..0..0....0..2....2..0....0..2....0..0....0..0....2..2....0..2....2..0....0..1
..2..0....2..0....0..1....0..2....2..1....1..2....0..0....1..1....2..1....1..2
..2..0....2..0....1..1....1..0....0..0....1..2....0..2....2..0....2..2....2..2
..2..0....0..1....1..0....0..2....2..2....1..1....0..0....1..2....2..1....1..0

Crossrefs

Sequence in context: A237772 A236819 A237099 * A237092 A206277 A236018

Adjacent sequences: A236809 A236810 A236811 * A236813 A236814 A236815

Keyword

nonn

Author

R. H. Hardin, Jan 31 2014

Status

approved