A253743 Number of (n+1)X(2+1) 0..2 arrays with every 2X2 subblock ne-sw antidiagonal difference nondecreasing horizontally and nw+se diagonal sum nondecreasing vertically

450, 2723, 16625, 75959, 305707, 1087364, 3598487, 11219006, 33417573, 95950526, 267699183, 729912815, 1953438640, 5149262462, 13406957125, 34558018931, 88348005194, 224349137386, 566585100420, 1424483824200, 3568296361053

Offset

1,1

Comments

Column 2 of A253749

Links

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

Formula

Empirical: a(n) = 9*a(n-1) -31*a(n-2) +46*a(n-3) -127*a(n-5) +260*a(n-6) -204*a(n-7) -196*a(n-8) +680*a(n-9) -740*a(n-10) +140*a(n-11) +901*a(n-12) -1486*a(n-13) +887*a(n-14) +429*a(n-15) -1605*a(n-16) +1729*a(n-17) -497*a(n-18) -945*a(n-19) +1656*a(n-20) -1324*a(n-21) +50*a(n-22) +1021*a(n-23) -1199*a(n-24) +685*a(n-25) +209*a(n-26) -744*a(n-27) +594*a(n-28) -176*a(n-29) -215*a(n-30) +343*a(n-31) -171*a(n-32) -14*a(n-33) +94*a(n-34) -87*a(n-35) +21*a(n-36) +19*a(n-37) -18*a(n-38) +9*a(n-39) -3*a(n-41) +a(n-42) for n>46

Example

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

Crossrefs

Sequence in context: A304511 A202197 A253750 * A253369 A253376 A253150

Adjacent sequences: A253740 A253741 A253742 * A253744 A253745 A253746

Keyword

nonn

Author

R. H. Hardin, Jan 11 2015

Status

approved