A245957 Number of length 7+3 0..n arrays with some pair in every consecutive four terms totalling exactly n.

548, 31577, 300304, 2141609, 7972932, 26526337, 67596992, 161991665, 335832580, 669329801, 1217929488, 2155659097, 3584230244, 5837790449, 9084731392, 13912683617, 20579766372, 30053056825, 42704873360, 60046213001, 82587911428

Offset: 1

Author

R. H. Hardin, Aug 08 2014

Keywords

• nonn

Comments

Row 7 of A245950

Examples

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

Links

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

Formula

Empirical: a(n) = 2*a(n-1) +5*a(n-2) -12*a(n-3) -9*a(n-4) +30*a(n-5) +5*a(n-6) -40*a(n-7) +5*a(n-8) +30*a(n-9) -9*a(n-10) -12*a(n-11) +5*a(n-12) +2*a(n-13) -a(n-14)