A220035 Number of 5 X n arrays of the minimum value of corresponding elements and their horizontal or diagonal neighbors in a random, but sorted with lexicographically nondecreasing rows and nonincreasing columns, 0..1 5 X n array.

6, 10, 21, 55, 111, 192, 302, 442, 618, 838, 1111, 1447, 1857, 2353, 2948, 3656, 4492, 5472, 6613, 7933, 9451, 11187, 13162, 15398, 17918, 20746, 23907, 27427, 31333, 35653, 40416, 45652, 51392, 57668, 64513, 71961, 80047, 88807, 98278, 108498

Offset

1,1

Comments

Row 5 of A220032.

Links

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

Formula

Empirical: a(n) = (1/24)*n^4 - (1/12)*n^3 + (95/24)*n^2 + (289/12)*n - 132 for n>6.

Conjectures from Colin Barker, Jul 30 2018: (Start)

G.f.: x*(6 - 20*x + 31*x^2 - 10*x^3 - 24*x^4 + 21*x^5 - 3*x^6 - 4*x^7 + 8*x^8 - 3*x^9 - x^10) / (1 - x)^5.

a(n) = 5*a(n-1) - 10*a(n-2) + 10*a(n-3) - 5*a(n-4) + a(n-5) for n>11.

(End)

Example

Some solutions for n=3:
..1..0..0....0..0..0....1..0..0....1..0..0....0..0..0....0..0..0....0..0..0
..1..1..1....1..0..0....1..0..0....1..0..0....1..0..0....1..1..0....0..0..0
..1..1..1....1..1..1....1..0..0....1..0..0....1..0..0....1..1..1....1..0..0
..1..1..1....1..1..1....1..1..1....1..0..0....1..0..0....1..1..1....1..0..0
..1..1..1....1..1..1....1..1..1....1..0..0....1..1..1....1..1..1....1..0..0

Crossrefs

Cf. A220032.

Sequence in context: A363675 A271511 A287993 * A083285 A082419 A102783

Adjacent sequences: A220032 A220033 A220034 * A220036 A220037 A220038

Keyword

nonn

Author

R. H. Hardin, Dec 03 2012

Status

approved