A253322 Number of (n+1)X(4+1) 0..1 arrays with every 2X2 subblock sum nondecreasing horizontally, vertically and antidiagonally ne-to-sw

286, 1026, 3787, 7744, 19312, 34660, 74953, 132376, 271506, 490768, 988800, 1844508, 3697682, 7081648, 14179216, 27648718, 55339218, 109108332, 218332780, 433235548, 866776878, 1726118188, 3452993316, 6889953894, 13781692502

Offset

1,1

Comments

Column 4 of A253326

Links

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

Formula

Empirical: a(n) = 4*a(n-1) +2*a(n-2) -26*a(n-3) +16*a(n-4) +62*a(n-5) -70*a(n-6) -62*a(n-7) +109*a(n-8) +14*a(n-9) -76*a(n-10) +16*a(n-11) +20*a(n-12) -8*a(n-13) for n>19

Example

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

Crossrefs

Sequence in context: A253329 A356422 A329392 * A241616 A204035 A235409

Adjacent sequences: A253319 A253320 A253321 * A253323 A253324 A253325

Keyword

nonn

Author

R. H. Hardin, Dec 30 2014

Status

approved