A109049 a(n) = lcm(n, 8).
0, 8, 8, 24, 8, 40, 24, 56, 8, 72, 40, 88, 24, 104, 56, 120, 16, 136, 72, 152, 40, 168, 88, 184, 24, 200, 104, 216, 56, 232, 120, 248, 32, 264, 136, 280, 72, 296, 152, 312, 40, 328, 168, 344, 88, 360, 184, 376, 48, 392, 200, 408, 104, 424, 216, 440, 56, 456, 232
Offset: 0
Links
- Amiram Eldar, Table of n, a(n) for n = 0..10000
- Index entries for linear recurrences with constant coefficients, signature (0,0,0,0,0,0,0,2,0,0,0,0,0,0,0,-1).
- Index entries for sequences related to lcm's.
Programs
-
Magma
[Lcm(n,8): n in [0..100]]; // Vincenzo Librandi, Apr 18 2011
-
Mathematica
LCM[Range[0,60],8] (* Harvey P. Dale, May 03 2019 *)
-
Sage
[lcm(n,8)for n in range(0, 59)] # Zerinvary Lajos, Jun 09 2009
Formula
a(n) = n*8/gcd(n, 8).
From R. J. Mathar, Apr 18 2011: (Start)
G.f.: 8*x*(x^2-x+1)*(x^12 + 2*x^11 + 4*x^10 + 3*x^9 + 4*x^8 + 4*x^7 + 7*x^6 + 4*x^5 + 4*x^4 + 3*x^3 + 4*x^2 + 2*x + 1) / ( (x-1)^2 *(1+x)^2 *(x^2+1)^2 *(x^4+1)^2 ).
Sum_{k=1..n} a(k) ~ (43/16) * n^2. - Amiram Eldar, Nov 26 2022