A250670 Number of (n+1)X(2+1) 0..3 arrays with nondecreasing x(i,j)+x(i,j-1) in the i direction and nondecreasing absolute value of x(i,j)-x(i-1,j) in the j direction

669, 5154, 34630, 210158, 1185860, 6325144, 32230991, 158164928, 752162284, 3484008326, 15783790118, 70176461116, 307081524576, 1325658002144, 5657123014959, 23904700805062, 100166248075189, 416720321036830

Offset

1,1

Comments

Column 2 of A250676

Links

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

Formula

Empirical: a(n) = 38*a(n-1) -678*a(n-2) +7552*a(n-3) -58895*a(n-4) +341814*a(n-5) -1531840*a(n-6) +5427992*a(n-7) -15445215*a(n-8) +35639986*a(n-9) -67056686*a(n-10) +103057344*a(n-11) -129153505*a(n-12) +131275346*a(n-13) -107173068*a(n-14) +69203560*a(n-15) -34519952*a(n-16) +12821856*a(n-17) -3336768*a(n-18) +542592*a(n-19) -41472*a(n-20) for n>28

Example

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

Crossrefs

Sequence in context: A105212 A067875 A224558 * A235101 A232388 A172963

Adjacent sequences: A250667 A250668 A250669 * A250671 A250672 A250673

Keyword

nonn

Author

R. H. Hardin, Nov 26 2014

Status

approved