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A224145 Number of n X 7 0..1 arrays with rows and antidiagonals unimodal and columns nondecreasing. 1
29, 239, 1037, 3296, 8838, 21183, 46586, 95455, 184222, 337727, 592178, 998751, 1627894, 2574399, 3963306, 5956703, 8761486, 12638143, 17910626, 24977375, 34323558, 46534591, 62311002, 82484703, 108036734, 140116543, 180062866 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Column 7 of A224146.

LINKS

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

FORMULA

Empirical: a(n) = (4/315)*n^7 + (4/45)*n^6 + (34/45)*n^5 + (29/9)*n^4 + (508/45)*n^3 + (1156/45)*n^2 + (1328/35)*n - 161 for n>4.

Conjectures from Colin Barker, Aug 28 2018: (Start)

G.f.: x*(29 + 7*x - 63*x^2 + 68*x^3 + 152*x^4 - 199*x^5 + 28*x^6 + 71*x^7 - 21*x^8 - 12*x^9 + 3*x^10 + x^11) / (1 - x)^8.

a(n) = 8*a(n-1) - 28*a(n-2) + 56*a(n-3) - 70*a(n-4) + 56*a(n-5) - 28*a(n-6) + 8*a(n-7) - a(n-8) for n>12.

(End)

EXAMPLE

Some solutions for n=3:

..0..0..0..0..0..0..0....0..0..0..0..0..0..0....0..0..0..0..0..0..0

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

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

CROSSREFS

Cf. A224146.

Sequence in context: A223837 A126426 A126425 * A225009 A177419 A142559

Adjacent sequences:  A224142 A224143 A224144 * A224146 A224147 A224148

KEYWORD

nonn

AUTHOR

R. H. Hardin, Mar 31 2013

STATUS

approved

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Last modified August 19 04:10 EDT 2019. Contains 326109 sequences. (Running on oeis4.)