A015633 Number of ordered triples of integers from [ 2,n ] with no global factor.

0, 2, 5, 14, 21, 41, 59, 89, 117, 171, 209, 286, 347, 432, 516, 651, 744, 914, 1042, 1219, 1382, 1634, 1806, 2091, 2323, 2629, 2895, 3300, 3562, 4026, 4386, 4843, 5249, 5802, 6204, 6869, 7380, 8025, 8569, 9388, 9928, 10830, 11516, 12347, 13104

Offset

2,2

Links

Reinhard Zumkeller, Table of n, a(n) for n = 2..250

Prog

(Haskell)
a015633 n = length [(x, y, z) | x <- [2..n], y <- [x..n], z <- [y..n],
                              gcd (gcd x y) z == 1]
-- Reinhard Zumkeller, Nov 28 2011

Crossrefs

Sequence in context: A118670 A228958 A216669 * A176191 A265248 A131661

Adjacent sequences: A015630 A015631 A015632 * A015634 A015635 A015636

Keyword

nonn

Author

Olivier Gérard

Status

approved