cp's OEIS Frontend

This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

A186986 Number of 10-element subsets of {1, 2, ..., n} having pairwise coprime elements.

Original entry on oeis.org

8, 8, 16, 16, 24, 24, 268, 268, 1569, 1857, 1952, 2010, 2156, 2176, 9265, 9596, 10167, 10339, 35489, 35589, 103267, 107303, 111153, 115675, 297827, 301611, 442057, 451649, 484539, 503173, 1150127, 1164141, 1290703, 1320491, 1413885, 1471627
Offset: 23

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Author

Alois P. Heinz, Mar 02 2011

Keywords

Examples

			a(24) = 8 because there are 8 10-element subsets of {1, 2, ..., 24} having pairwise coprime elements: {1,2,3,5,7,11,13,17,19,23}, {1,2,5,7,9,11,13,17,19,23}, {1,3,4,5,7,11,13,17,19,23}, {1,3,5,7,8,11,13,17,19,23}, {1,3,5,7,11,13,16,17,19,23}, {1,4,5,7,9,11,13,17,19,23}, {1,5,7,8,9,11,13,17,19,23}, {1,5,7,9,11,13,16,17,19,23}.
		

Crossrefs

Column 10 of triangle A186974. Partial sums of A186981.