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A224042
Number of 6 X n 0..1 arrays with antidiagonals unimodal and rows and diagonals nondecreasing
1
64, 377, 848, 1422, 2149, 3107, 4395, 6124, 8439, 11527, 15626, 21035, 28125, 37351, 49265, 64530, 83935, 108411, 139048, 177113, 224069, 281595, 351607, 436280, 538071, 659743, 804390, 975463, 1176797, 1412639, 1687677, 2007070, 2376479
OFFSET
1,1
COMMENTS
Row 6 of A224038.
LINKS
FORMULA
Empirical: a(n) = (1/720)*n^6 + (1/240)*n^5 + (35/144)*n^4 + (127/48)*n^3 + (1249/45)*n^2 + (3727/20)*n + 6 for n>4.
Conjectures from Colin Barker, Aug 26 2018: (Start)
G.f.: x*(64 - 71*x - 447*x^2 + 1163*x^3 - 952*x^4 + 97*x^5 + 216*x^6 - 72*x^7 + 33*x^8 - 45*x^9 + 15*x^10) / (1 - x)^7.
a(n) = 7*a(n-1) - 21*a(n-2) + 35*a(n-3) - 35*a(n-4) + 21*a(n-5) - 7*a(n-6) + a(n-7) for n>11.
(End)
EXAMPLE
Some solutions for n=3:
..0..0..0....1..1..1....1..1..1....0..0..0....0..0..0....0..0..0....1..1..1
..0..0..1....0..1..1....1..1..1....1..1..1....0..0..0....0..0..0....0..1..1
..0..0..0....0..1..1....0..1..1....1..1..1....0..0..0....0..0..0....0..0..1
..0..0..1....0..1..1....0..1..1....0..1..1....0..0..0....0..0..1....0..0..1
..0..0..0....1..1..1....0..1..1....1..1..1....0..0..1....0..1..1....0..0..0
..0..1..1....1..1..1....1..1..1....0..1..1....0..1..1....1..1..1....0..0..0
CROSSREFS
Cf. A224038.
Sequence in context: A017486 A344302 A105918 * A188840 A188703 A297343
KEYWORD
nonn
AUTHOR
R. H. Hardin, Mar 30 2013
STATUS
approved