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A223952 Number of 5 X n 0..1 arrays with diagonals and antidiagonals unimodal and rows nondecreasing. 1
32, 243, 596, 1062, 1821, 3115, 5233, 8564, 13613, 21017, 31561, 46194, 66045, 92439, 126913, 171232, 227405, 297701, 384665, 491134, 620253, 775491, 960657, 1179916, 1437805, 1739249, 2089577, 2494538, 2960317, 3493551, 4101345, 4791288, 5571469 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Row 5 of A223949.

LINKS

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

FORMULA

Empirical: a(n) = (2/15)*n^5 + (1/6)*n^4 + (23/6)*n^3 + (89/6)*n^2 + (1501/30)*n + 200 for n>3.

Conjectures from Colin Barker, Aug 24 2018: (Start)

G.f.: x*(32 + 51*x - 382*x^2 + 491*x^3 + 9*x^4 - 348*x^5 + 132*x^6 + 68*x^7 - 37*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..1..1....1..1..1....0..0..1....0..0..1....0..0..0....0..0..0....0..1..1

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

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

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

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

CROSSREFS

Cf. A223949.

Sequence in context: A111442 A104782 A186774 * A224136 A250363 A346637

Adjacent sequences:  A223949 A223950 A223951 * A223953 A223954 A223955

KEYWORD

nonn

AUTHOR

R. H. Hardin, Mar 29 2013

STATUS

approved

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Last modified November 29 20:40 EST 2021. Contains 349416 sequences. (Running on oeis4.)