A184707 Number of strings of numbers x(i=1..7) in 0..n with sum i*x(i) equal to n*7.

5, 35, 154, 504, 1349, 3142, 6575, 12688, 22923, 39266, 64315, 101460, 154942, 230095, 333394, 472735, 657496, 898863, 1209864, 1605777, 2104139, 2725200, 3491939, 4430572, 5570527, 6945053, 8591154, 10550253, 12868125, 15595628

Offset: 1

Author

R. H. Hardin Jan 20 2011

Keywords

• nonn

Comments

Row 7 of A184703

Examples

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

Links

• R. H. Hardin, Table of n, a(n) for n = 1..200

Formula

Empirical: a(n)=a(n-1)+a(n-2)-a(n-5)-a(n-7)-a(n-8)+a(n-10)+a(n-11)+2*a(n-12)-2*a(n-16)-a(n-17)-a(n-18)+a(n-20)+a(n-21)+a(n-23)-a(n-26)-a(n-27)+a(n-28)