The OEIS mourns the passing of Jim Simons and is grateful to the Simons Foundation for its support of research in many branches of science, including the OEIS.
login
The OEIS is supported by the many generous donors to the OEIS Foundation.

 

Logo
Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A038039 a(n) = Sum_{d|n} (2^d*3^(n/d)). 1

%I #14 Oct 06 2020 02:09:48

%S 6,30,78,246,582,1830,4758,14358,41118,122430,360438,1079742,3213222,

%T 9624990,28798926,86319894,258673542,775718310,2326095798,6976966422,

%U 20927018814,62775429150,188311523478,564911643486,1694677889958

%N a(n) = Sum_{d|n} (2^d*3^(n/d)).

%e For n = 3, the divisors are 1 and 3, the sum is 2^1 * 3^3 + 2^3 * 3^1 = 54 + 24 = 78.

%t Table[Total[2^Divisors[n] 3^(n/Divisors[n])],{n,30}] (* _Harvey P. Dale_, Nov 08 2017 *)

%o (PARI) a(n) = sumdiv(n, d, 2^d*3^(n/d)); \\ _Michel Marcus_, Oct 05 2020

%Y Equals 6*A034735(n).

%K nonn,easy

%O 1,1

%A _Christian G. Bower_

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

License Agreements, Terms of Use, Privacy Policy. .

Last modified May 12 18:22 EDT 2024. Contains 372494 sequences. (Running on oeis4.)