A203657 Number of (n+1)X2 0..7 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

1212, 27966, 557544, 9592248, 146861704, 2050339423, 26569429480, 323824032048, 3749613354500, 41576091707436, 444241382108136, 4597646074173360, 46283153123300304, 454783873288441005, 4374858039450660168

Offset

1,1

Comments

Column 1 of A203661

Links

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

Formula

Empirical: a(n) = 70*a(n-1) -2275*a(n-2) +45612*a(n-3) -632289*a(n-4) +6438138*a(n-5) -49938467*a(n-6) +302065016*a(n-7) -1446908771*a(n-8) +5543625850*a(n-9) -17090839633*a(n-10) +42516502924*a(n-11) -85337511267*a(n-12) +137796276966*a(n-13) -177910179993*a(n-14) +181835622416*a(n-15) -144879499352*a(n-16) +87918207776*a(n-17) -39188297232*a(n-18) +12080293632*a(n-19) -2298481920*a(n-20) +203212800*a(n-21)

Example

Some solutions for n=5
..6..1....1..1....7..2....0..5....0..2....5..2....2..3....7..7....6..6....0..3
..1..6....3..3....2..7....2..3....5..3....1..6....2..7....7..7....5..7....3..4
..2..5....4..4....2..7....7..0....5..7....7..2....5..4....7..7....5..7....5..2
..3..4....5..5....2..7....0..7....5..7....2..7....2..7....7..7....5..7....5..2
..0..7....6..7....3..6....3..4....5..7....2..7....7..2....7..7....7..5....1..6
..1..6....6..7....4..5....2..5....5..7....5..4....7..5....7..7....5..7....0..7

Crossrefs

Sequence in context: A204339 A204332 A203661 * A250159 A184464 A204331

Adjacent sequences: A203654 A203655 A203656 * A203658 A203659 A203660

Keyword

nonn

Author

R. H. Hardin Jan 04 2012

Status

approved