A219212 Number of nX3 arrays of the minimum value of corresponding elements and their horizontal, vertical, diagonal or antidiagonal neighbors in a random, but sorted with lexicographically nondecreasing rows and columns, 0..2 nX3 array

6, 7, 37, 113, 345, 955, 2508, 6303, 15251, 35567, 80116, 174791, 370485, 765038, 1542719, 3044020, 5887082, 11175742, 20850733, 38274020, 69187496, 123264742, 216590254, 375571230, 643035886, 1087631035, 1818143164, 3005088770

Offset

1,1

Comments

Column 3 of A219217

Links

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

Formula

Empirical: a(n) = (1/20922789888000)*n^16 - (1/201180672000)*n^15 + (317/1046139494400)*n^14 - (409/37362124800)*n^13 + (28001/114960384000)*n^12 - (1031/513216000)*n^11 - (342367/7315660800)*n^10 + (3153317/1828915200)*n^9 - (2891026769/146313216000)*n^8 - (68017459/2612736000)*n^7 + (19662024383/5748019200)*n^6 - (4114129211/102643200)*n^5 + (80159944394683/435891456000)*n^4 + (166453839809/1397088000)*n^3 - (2770211114939/605404800)*n^2 + (3811038289/240240)*n - 15029 for n>11

Example

Some solutions for n=3
..0..0..2....0..0..0....0..0..2....1..1..1....0..0..1....1..1..2....0..0..1
..0..0..1....0..0..0....0..0..2....1..0..0....0..0..1....1..1..1....0..0..0
..1..1..1....1..0..0....1..1..2....1..0..0....0..0..1....1..1..1....0..0..0

Crossrefs

Sequence in context: A013627 A248850 A294728 * A301904 A152119 A041080

Adjacent sequences: A219209 A219210 A219211 * A219213 A219214 A219215

Keyword

nonn

Author

R. H. Hardin Nov 14 2012

Status

approved