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A203958 Number of (n+1) X 2 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) such that rows of b(i,j) and columns of c(i,j) are lexicographically nondecreasing. 1
32, 121, 447, 1579, 5352, 17559, 56219, 176797, 548760, 1687165, 5151519, 15651063, 47379056, 143054539, 431129547, 1297582777, 3901661040, 11723857281, 35211417503, 105718138339, 317330575512, 952360824991, 2857854226587 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Column 1 of A203965.

LINKS

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

FORMULA

Empirical: a(n) = 10*a(n-1) -40*a(n-2) +82*a(n-3) -91*a(n-4) +52*a(n-5) -12*a(n-6).

Empirical g.f.: x*(32 - 199*x + 517*x^2 - 675*x^3 + 432*x^4 - 108*x^5) / ((1 - x)^3*(1 - 2*x)^2*(1 - 3*x)). - Colin Barker, Jun 06 2018

EXAMPLE

Some solutions for n=4:

..1..2....2..0....0..0....1..1....0..2....0..2....1..2....2..1....2..1....2..2

..1..2....0..2....2..2....1..1....0..2....1..1....1..2....1..2....1..2....2..2

..1..2....2..0....2..2....0..2....2..0....1..1....2..1....2..2....2..1....2..2

..1..2....0..2....2..2....2..1....0..2....0..2....1..2....2..2....1..2....2..2

..1..2....1..1....2..2....2..1....1..2....1..2....2..1....2..2....2..1....2..2

CROSSREFS

Cf. A203965.

Sequence in context: A297698 A223314 A203965 * A005903 A271532 A264480

Adjacent sequences:  A203955 A203956 A203957 * A203959 A203960 A203961

KEYWORD

nonn

AUTHOR

R. H. Hardin, Jan 08 2012

STATUS

approved

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Last modified October 17 16:47 EDT 2018. Contains 316287 sequences. (Running on oeis4.)