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A203723 Number of (n+1)X4 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
326, 1632, 6249, 20290, 58048, 151649, 367595, 839916, 1825184, 3804580, 7650824, 14922063, 28339038, 52596875, 95678477, 171041225, 301149679, 523280917, 898900092, 1528951772, 2578559796, 4317146589, 7183260955, 11889652446 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Column 3 of A203728

LINKS

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

FORMULA

Empirical: a(n) = 9*a(n-1) -30*a(n-2) +31*a(n-3) +67*a(n-4) -220*a(n-5) +136*a(n-6) +300*a(n-7) -546*a(n-8) +78*a(n-9) +572*a(n-10) -494*a(n-11) -130*a(n-12) +404*a(n-13) -152*a(n-14) -100*a(n-15) +99*a(n-16) -15*a(n-17) -14*a(n-18) +7*a(n-19) -a(n-20) for n>23

EXAMPLE

Some solutions for n=4

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

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

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

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

..2..2..2..2....2..2..2..2....2..2..2..2....2..2..2..2....2..2..2..2

CROSSREFS

Sequence in context: A138816 A138817 A158271 * A097737 A236822 A126311

Adjacent sequences:  A203720 A203721 A203722 * A203724 A203725 A203726

KEYWORD

nonn

AUTHOR

R. H. Hardin Jan 05 2012

STATUS

approved

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Last modified October 6 05:47 EDT 2022. Contains 357261 sequences. (Running on oeis4.)