A253528 Number of (n+1)X(3+1) 0..2 arrays with every 2X2 subblock antidiagonal maximum minus diagonal minimum nondecreasing horizontally and diagonal maximum minus antidiagonal minimum nondecreasing vertically

1963, 9255, 22418, 62237, 142679, 327147, 700492, 1477077, 3032758, 6133637, 12288617, 24390278, 48315319, 95291840, 188147188, 371030185, 733190192, 1449380597, 2871171233, 5693041370, 11308044039, 22483109832, 44759818386

Offset

1,1

Comments

Column 3 of A253533

Links

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

Formula

Empirical: a(n) = 9*a(n-1) -28*a(n-2) +14*a(n-3) +120*a(n-4) -268*a(n-5) +16*a(n-6) +648*a(n-7) -734*a(n-8) -370*a(n-9) +1320*a(n-10) -604*a(n-11) -812*a(n-12) +996*a(n-13) -80*a(n-14) -472*a(n-15) +279*a(n-16) +17*a(n-17) -76*a(n-18) +30*a(n-19) -4*a(n-20) for n>29

Example

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

Crossrefs

Sequence in context: A072598 A159213 A056094 * A235966 A252380 A251023

Adjacent sequences: A253525 A253526 A253527 * A253529 A253530 A253531

Keyword

nonn

Author

R. H. Hardin, Jan 03 2015

Status

approved