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A109048
a(n) = lcm(n, 7).
3
0, 7, 14, 21, 28, 35, 42, 7, 56, 63, 70, 77, 84, 91, 14, 105, 112, 119, 126, 133, 140, 21, 154, 161, 168, 175, 182, 189, 28, 203, 210, 217, 224, 231, 238, 35, 252, 259, 266, 273, 280, 287, 42, 301, 308, 315, 322, 329, 336, 49, 350, 357, 364, 371, 378, 385, 56
OFFSET
0,2
FORMULA
a(n) = n*7/gcd(n, 7).
a(n) = 7*A106608(n) = 7*n/A109010(n). - R. J. Mathar, Apr 18 2011
Sum_{k=1..n} a(k) ~ (43/14) * n^2. - Amiram Eldar, Nov 26 2022
Sum_{n>=1} (-1)^(n+1)/a(n) = 13*log(2)/49. - Amiram Eldar, Sep 08 2023
MATHEMATICA
LCM[Range[0, 100], 7] (* Wesley Ivan Hurt, Nov 17 2022 *)
PROG
(Sage) [lcm(n, 7)for n in range(0, 57)] # Zerinvary Lajos, Jun 09 2009
(Magma) [Lcm(n, 7): n in [0..100]]; // Vincenzo Librandi, Apr 18 2011
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
Mitch Harris, Jun 18 2005
STATUS
approved