A070293 a(n) = lcm(30,n)/gcd(30,n).

30, 15, 10, 30, 6, 5, 210, 60, 30, 3, 330, 10, 390, 105, 2, 120, 510, 15, 570, 6, 70, 165, 690, 20, 30, 195, 90, 210, 870, 1, 930, 240, 110, 255, 42, 30, 1110, 285, 130, 12, 1230, 35, 1290, 330, 6, 345, 1410, 40, 1470, 15

Offset: 1

Author

Amarnath Murthy, May 10 2002

Keywords

• easy
• nonn

Crossrefs

Cf. A130724, A188134, A283442, A283443, A070290, A070291, A070292.

Programs

Mathematica

Table[LCM[30,n]/GCD[30,n],{n,50}]  (* Harvey P. Dale, Apr 17 2011 *)

Formula

Sum_{k=1..n} a(k) ~ (1919/360)*n^2. - Amiram Eldar, Oct 07 2023

Extensions

More terms from Harvey P. Dale, Apr 17 2011