login
The OEIS Foundation is supported by donations from users of the OEIS and by a grant from the Simons Foundation.

 

Logo


Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A015633 Number of ordered triples of integers from [ 2,n ] with no global factor. 1
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 (list; graph; refs; listen; history; text; internal format)
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

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recent
The OEIS Community | Maintained by The OEIS Foundation Inc.

License Agreements, Terms of Use, Privacy Policy. .

Last modified July 13 13:48 EDT 2020. Contains 335688 sequences. (Running on oeis4.)