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A204649 Number of (n+1) X 7 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) nondecreasing in column and row directions, respectively. 1
132, 200, 434, 938, 1918, 3702, 6780, 11868, 19969, 32450, 51134, 78404, 117324, 171774, 246604, 347804, 482695, 660138, 890766, 1187236, 1564506, 2040134, 2634604, 3371676, 4278765, 5387346, 6733390, 8357828, 10307048, 12633422 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Column 6 of A204651.

LINKS

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

FORMULA

Empirical: a(n) = 7*a(n-1) -20*a(n-2) +28*a(n-3) -14*a(n-4) -14*a(n-5) +28*a(n-6) -20*a(n-7) +7*a(n-8) -a(n-9) for n>13.

Empirical g.f.: x*(132 - 724*x + 1674*x^2 - 1796*x^3 + 280*x^4 + 1532*x^5 - 1858*x^6 + 992*x^7 - 255*x^8 + 15*x^9 + 26*x^10 - 22*x^11 + 6*x^12) / ((1 - x)^8*(1 + x)). - Colin Barker, Jun 08 2018

EXAMPLE

Some solutions for n=5:

..0..0..0..1..1..1..1....0..0..0..0..0..0..1....0..0..0..0..0..0..0

..0..0..1..1..1..1..1....0..0..0..0..0..0..1....0..0..0..0..0..1..1

..0..0..1..1..1..1..1....0..0..0..0..0..0..1....0..0..1..1..1..1..1

..0..0..1..1..1..1..1....0..0..0..0..1..1..1....0..0..1..1..1..1..1

..0..0..1..1..1..1..1....0..0..0..1..1..1..1....0..1..1..1..1..1..1

..0..1..1..1..1..1..1....1..1..1..1..1..1..1....1..1..1..1..1..1..1

CROSSREFS

Cf. A204651.

Sequence in context: A030026 A102474 A015235 * A224548 A253510 A253503

Adjacent sequences:  A204646 A204647 A204648 * A204650 A204651 A204652

KEYWORD

nonn

AUTHOR

R. H. Hardin, Jan 17 2012

STATUS

approved

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Last modified April 23 07:51 EDT 2019. Contains 322381 sequences. (Running on oeis4.)