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A224131
Number of n X 6 0..1 arrays with rows nondecreasing and antidiagonals unimodal.
1
7, 49, 269, 1279, 5648, 24095, 101412, 425246, 1783229, 7484923, 31443217, 132153826, 555559627, 2335689630, 9819848422, 41284852413, 173569002429, 729710418743, 3067802281464, 12897441557475, 54222509714920
OFFSET
1,1
COMMENTS
Column 6 of A224133.
LINKS
FORMULA
Empirical: a(n) = 7*a(n-1) - 14*a(n-2) + 9*a(n-3) + 4*a(n-5) + 16*a(n-6).
Empirical g.f.: x*(7 + 24*x^2 + 19*x^3 + 20*x^4 + 16*x^5) / (1 - 7*x + 14*x^2 - 9*x^3 - 4*x^5 - 16*x^6). - Colin Barker, Aug 27 2018
EXAMPLE
Some solutions for n=3:
..1..1..1..1..1..1....1..1..1..1..1..1....0..0..0..0..1..1....0..0..0..0..1..1
..0..1..1..1..1..1....0..1..1..1..1..1....0..0..0..1..1..1....0..0..0..0..1..1
..0..0..0..0..1..1....0..1..1..1..1..1....0..1..1..1..1..1....0..0..0..0..0..0
CROSSREFS
Cf. A224133.
Sequence in context: A203059 A203383 A293887 * A218266 A213295 A189258
KEYWORD
nonn
AUTHOR
R. H. Hardin, Mar 31 2013
STATUS
approved