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A224041 Number of 5 X n 0..1 arrays with antidiagonals unimodal and rows and diagonals nondecreasing. 1
32, 144, 298, 488, 734, 1064, 1505, 2091, 2864, 3875, 5185, 6866, 9002, 11690, 15041, 19181, 24252, 30413, 37841, 46732, 57302, 69788, 84449, 101567, 121448, 144423, 170849, 201110, 235618, 274814, 319169, 369185, 425396, 488369, 558705, 637040 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Row 5 of A224038.

LINKS

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

FORMULA

Empirical: a(n) = (1/120)*n^5 + (1/24)*n^4 + (25/24)*n^3 + (227/24)*n^2 + (1289/20)*n - 7 for n>3.

Conjectures from Colin Barker, Aug 26 2018: (Start)

G.f.: x*(32 - 48*x - 86*x^2 + 220*x^3 - 124*x^4 - 12*x^5 + 9*x^6 + 17*x^7 - 7*x^8) / (1 - x)^6.

a(n) = 6*a(n-1) - 15*a(n-2) + 20*a(n-3) - 15*a(n-4) + 6*a(n-5) - a(n-6) for n>9.

(End)

EXAMPLE

Some solutions for n=3:

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

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

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

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

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

CROSSREFS

Cf. A224038.

Sequence in context: A159763 A100164 A048191 * A188839 A188702 A297342

Adjacent sequences:  A224038 A224039 A224040 * A224042 A224043 A224044

KEYWORD

nonn

AUTHOR

R. H. Hardin, Mar 30 2013

STATUS

approved

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Last modified January 28 22:35 EST 2020. Contains 331328 sequences. (Running on oeis4.)