A268266 Number of length-(7+1) 0..n arrays with new repeated values introduced in sequential order starting with zero.

129, 1918, 18804, 126591, 619490, 2377935, 7594224, 21042479, 52119726, 117925215, 247685420, 488872479, 915404154, 1638353711, 2819638440, 4689195855, 7566196934, 11884886079, 18225677796, 27352180415, 40254857490

Offset: 1

Author

R. H. Hardin, Jan 29 2016

Keywords

• nonn

Comments

Row 7 of A268261.

Examples

			Some solutions for n=4
..2....0....0....3....2....1....0....2....0....1....4....3....1....3....1....1
..3....4....4....1....3....0....1....4....2....0....1....1....3....0....0....2
..4....3....3....3....1....1....3....0....4....4....2....4....2....2....4....0
..1....2....0....1....4....2....4....0....2....1....0....2....4....1....0....0
..3....3....4....0....2....4....0....4....4....0....3....1....2....2....0....2
..0....4....1....3....1....2....0....2....1....3....0....3....4....4....1....3
..3....0....0....0....2....1....1....1....0....0....2....2....1....2....4....0
..0....0....1....4....3....2....1....2....2....3....0....1....3....4....2....3
		

Links

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

Crossrefs

Cf. A268261.

Formula

Empirical: a(n) = n^8 + n^7 + 7*n^6 + 6*n^5 + 30*n^4 + 20*n^3 + 50*n^2 + 20*n + 15 for n>2