A203447 Number of (n+1)X4 0..1 arrays with column and row pair sums b(i,j)=a(i,j)+a(i,j-1) and c(i,j)=a(i,j)+a(i-1,j) such that rows of b(i,j) and columns of c(i,j) are lexicographically nondecreasing

32, 80, 321, 1177, 4200, 13777, 42112, 120522, 325918, 838830, 2069033, 4920266, 11341301, 25458409, 55884995, 120402167, 255405453, 534912676, 1108733446, 2279008959, 4653553590, 9452873217, 19124629018, 38573101568, 77618789808

Offset

1,1

Comments

Column 3 of A203452

Links

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

Formula

Empirical: a(n) = 13*a(n-1) -76*a(n-2) +262*a(n-3) -583*a(n-4) +847*a(n-5) -726*a(n-6) +132*a(n-7) +561*a(n-8) -869*a(n-9) +704*a(n-10) -362*a(n-11) +119*a(n-12) -23*a(n-13) +2*a(n-14) for n>17

Example

Some solutions for n=7
..0..0..0..0....0..0..0..0....0..0..0..1....0..0..0..0....0..0..0..0
..0..0..0..1....0..0..0..1....0..0..0..1....0..0..1..1....0..0..0..0
..0..0..1..0....0..0..1..1....0..0..0..1....0..0..1..1....0..0..0..1
..0..0..1..0....0..1..0..1....0..0..1..0....0..1..0..1....0..0..0..1
..0..0..1..1....1..0..1..1....0..0..1..1....0..1..1..0....0..0..1..0
..0..1..0..0....1..0..1..1....0..1..1..0....1..1..0..0....0..0..1..1
..0..1..0..0....0..1..1..0....0..1..1..0....1..1..0..0....1..1..0..0
..1..1..1..1....1..1..0..1....1..1..1..0....1..1..1..1....1..1..1..0

Crossrefs

Sequence in context: A209378 A182466 A234133 * A340701 A043410 A044170

Adjacent sequences: A203444 A203445 A203446 * A203448 A203449 A203450

Keyword

nonn

Author

R. H. Hardin Jan 02 2012

Status

approved