A229797 Number of 4X4 0..n arrays with rows and columns in lexicographically nondecreasing order.

650, 250841, 21907055, 733861607, 13111482259, 150943642765, 1257194266246, 8170451731089, 43642376268844, 198859490805437, 794550500198885, 2842727725991231, 9257049674121653, 27794351169785161, 77754305616698860

Offset: 1

Author

R. H. Hardin, Sep 29 2013

Keywords

• nonn

Comments

Row 4 of A229794

Examples

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

Links

• R. H. Hardin, Table of n, a(n) for n = 1..41

Formula

Empirical: a(n) = (1/252)*n^16 + (17/252)*n^15 + (1349/2520)*n^14 + (26531/10080)*n^13 + (2597/288)*n^12 + (691/30)*n^11 + (694109/15120)*n^10 + (2229581/30240)*n^9 + (5469/56)*n^8 + (546263/5040)*n^7 + (73249/720)*n^6 + (7297/90)*n^5 + (47305/864)*n^4 + (16739/540)*n^3 + (36263/2520)*n^2 + (533/105)*n + 1