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proposed

reviewed

editing

proposed

Multiplicative with a(2^e) = 2^max(0, e-1), a(3^e) = 3^max(0,e-2), and a(p^e) = p^e otherwise.

Cf. A227042.

<a href="/index/Rec#order_36">Index entries for linear recurrences with constant coefficients</a>, signature (0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,2,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,-1).

nonn,easy,frac,mult,changed

From Amiram Eldar, Nov 25 2022: (Start)

Multiplicative with a(2^e) = 2^max(0, e-1), a(3^e) = 3^max(0,e-2), a(p^e) = p^e otherwise.

Sum_{k=1..n} a(k) ~ (61/216) * n^2. (End)

approved

editing

(MAGMAMagma) [Numerator(n/(n+18)): n in [0..100]]; // Vincenzo Librandi, Apr 18 2011

OEIS Server: https://oeis.org/edit/global/2944

(Sage) [lcm(n, 18)/18 for n in xrangerange(0, 100)] # Zerinvary Lajos, Jun 12 2009

OEIS Server: https://oeis.org/edit/global/2837

proposed

approved