A253527 Number of (n+1)X(2+1) 0..2 arrays with every 2X2 subblock antidiagonal maximum minus diagonal minimum nondecreasing horizontally and diagonal maximum minus antidiagonal minimum nondecreasing vertically

459, 2722, 9255, 27070, 71333, 176266, 416901, 955594, 2141571, 4715371, 10248721, 22049172, 47076283, 99907559, 211046947, 444155161, 931919916, 1950390796, 4073131178, 8490131272, 17667326091, 36708441877, 76165100413, 157828885543

Offset

1,1

Comments

Column 2 of A253533

Links

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

Formula

Empirical: a(n) = 7*a(n-1) -12*a(n-2) -24*a(n-3) +97*a(n-4) -31*a(n-5) -238*a(n-6) +262*a(n-7) +225*a(n-8) -495*a(n-9) +16*a(n-10) +428*a(n-11) -193*a(n-12) -161*a(n-13) +138*a(n-14) +6*a(n-15) -32*a(n-16) +8*a(n-17) for n>27

Example

Some solutions for n=4
..1..1..2....1..1..0....2..1..2....2..1..1....1..0..1....0..0..1....1..0..2
..1..1..1....2..1..0....1..1..1....2..1..0....2..1..0....1..1..1....2..1..0
..1..1..1....1..2..1....1..2..2....2..1..0....1..1..0....2..2..2....1..2..1
..1..1..1....0..1..0....0..0..0....1..1..0....0..1..0....1..1..0....0..1..0
..0..1..2....0..2..1....2..2..2....0..2..1....2..2..0....0..1..2....0..2..2

Crossrefs

Sequence in context: A055159 A124694 A227754 * A183964 A221816 A048923

Adjacent sequences: A253524 A253525 A253526 * A253528 A253529 A253530

Keyword

nonn

Author

R. H. Hardin, Jan 03 2015

Status

approved