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A203724
Number of (n+1)X5 0..2 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) nondecreasing in column and row directions, respectively
1
888, 4737, 20290, 72777, 230014, 656441, 1728140, 4246268, 9847415, 21700159, 45744109, 92663818, 181178545, 343044939, 630954514, 1130114352, 1975727787, 3377874220, 5657695118, 9297612083, 15012132902, 23843994305, 37296211132
OFFSET
1,1
COMMENTS
Column 4 of A203728
LINKS
FORMULA
Empirical: a(n) = 9*a(n-1) -30*a(n-2) +30*a(n-3) +75*a(n-4) -243*a(n-5) +152*a(n-6) +360*a(n-7) -690*a(n-8) +130*a(n-9) +780*a(n-10) -780*a(n-11) -130*a(n-12) +690*a(n-13) -360*a(n-14) -152*a(n-15) +243*a(n-16) -75*a(n-17) -30*a(n-18) +30*a(n-19) -9*a(n-20) +a(n-21) for n>26
EXAMPLE
Some solutions for n=4
..1..2..2..2..2....1..1..1..2..1....1..2..2..2..2....0..1..1..1..0
..1..2..2..2..2....1..1..2..1..2....1..2..2..2..2....2..1..1..1..2
..1..2..2..2..2....0..2..1..2..1....1..2..2..2..2....1..2..2..2..2
..2..2..2..2..2....1..1..2..1..2....1..2..2..2..2....1..2..2..2..2
..2..2..2..2..2....0..2..1..2..1....1..2..2..2..2....2..2..2..2..2
CROSSREFS
Sequence in context: A043523 A066270 A236981 * A006915 A178270 A183751
KEYWORD
nonn
AUTHOR
R. H. Hardin Jan 05 2012
STATUS
approved