A236791 Number of (n+1)X(1+1) 0..2 arrays with the maximum plus the upper median plus the minimum of every 2X2 subblock equal

81, 255, 825, 2817, 9717, 34317, 122305, 442285, 1612085, 5935493, 21990145, 82051485, 307574133, 1158698629, 4379531169, 16610367645, 63145291189, 240620562981, 918393173569, 3511019670621, 13437773070709, 51488379790533

Offset

1,1

Comments

Column 1 of A236798

Links

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

Formula

Empirical: a(n) = 8*a(n-1) +8*a(n-2) -204*a(n-3) +224*a(n-4) +1972*a(n-5) -3810*a(n-6) -9220*a(n-7) +24389*a(n-8) +20868*a(n-9) -81294*a(n-10) -13536*a(n-11) +150316*a(n-12) -33360*a(n-13) -148072*a(n-14) +72384*a(n-15) +63616*a(n-16) -48128*a(n-17) -2816*a(n-18) +8192*a(n-19) -1536*a(n-20)

Example

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

Crossrefs

Sequence in context: A236798 A237067 A236782 * A237060 A361179 A340697

Adjacent sequences: A236788 A236789 A236790 * A236792 A236793 A236794

Keyword

nonn

Author

R. H. Hardin, Jan 31 2014

Status

approved