A186989 Number of subsets of {1, 2, ..., n} containing n and having <=5 pairwise coprime elements.

1, 2, 4, 4, 12, 4, 28, 16, 32, 12, 110, 16, 209, 46, 69, 98, 507, 57, 828, 141, 277, 193, 1591, 163, 1289, 413, 1101, 441, 3785, 163, 5164, 1479, 1736, 1187, 2540, 609, 9561, 1879, 3086, 1304, 14298, 738, 18084, 3322, 3913, 3888, 25430

Offset: 1

Author

Alois P. Heinz, Mar 03 2011

Keywords

• nonn

Examples

			a(10) = 12 because there are 12 subsets of {1, 2, ..., 10} containing 10 and having <=5 pairwise coprime elements: {10}, {1,10}, {3,10}, {7,10}, {9,10}, {1,3,10}, {1,7,10}, {1,9,10}, {3,7,10}, {7,9,10}, {1,3,7,10}, {1,7,9,10}. There is no subset with exactly 5 elements here.
		

Links

• Alois P. Heinz, Table of n, a(n) for n = 1..200

Crossrefs

Column 5 of triangle A186975. Sum of A186988 and A186976.