A235574 Number of (n+1)X(1+1) 0..3 arrays with the difference of the upper and lower median value of each 2X2 subblock in lexicographically nondecreasing order rowwise and columnwise

256, 2894, 28978, 268448, 2377726, 20374112, 170668898, 1404828230, 11413317704, 91766116488, 731808519584, 5797224998624, 45676273081688, 358272122900606, 2799733458956666, 21810268527215416, 169456934940212246

Offset

1,1

Comments

Column 1 of A235577

Links

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

Formula

Empirical: a(n) = 16*a(n-1) -28*a(n-2) -667*a(n-3) +2717*a(n-4) +9004*a(n-5) -55228*a(n-6) -31261*a(n-7) +479324*a(n-8) -256716*a(n-9) -1907096*a(n-10) +2311456*a(n-11) +2958880*a(n-12) -6158976*a(n-13) +410112*a(n-14) +5138432*a(n-15) -3686400*a(n-16) +786432*a(n-17)

Example

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

Crossrefs

Sequence in context: A236585 A235818 A235577 * A235824 A235582 A236657

Adjacent sequences: A235571 A235572 A235573 * A235575 A235576 A235577

Keyword

nonn

Author

R. H. Hardin, Jan 12 2014

Status

approved