The OEIS Foundation is supported by donations from users of the OEIS and by a grant from the Simons Foundation.

 Hints (Greetings from The On-Line Encyclopedia of Integer Sequences!)
 A034719 Dirichlet convolution of powers of 3 (3,9,27,...) with themselves. 1
 9, 54, 162, 567, 1458, 4860, 13122, 40824, 118827, 358668, 1062882, 3206142, 9565938, 28737180, 86106564, 258404985, 774840978, 2324916594, 6973568802, 20921808654, 62762237316, 188289546300, 564859072962, 1694587257216 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 LINKS FORMULA a(n) ~ 2 * 3^(n+1). - Vaclav Kotesovec, Sep 11 2019 G.f.: Sum_{k>=1} 3^(k+1)*x^k / (1 - 3*x^k). - Ilya Gutkovskiy, Sep 22 2020 MATHEMATICA Table[Sum[3^(d + n/d), {d, Divisors[n]}], {n, 1, 30}] (* Vaclav Kotesovec, Sep 11 2019 *) CROSSREFS Equals 9 * A034751(n). Sequence in context: A225791 A093846 A152994 * A013567 A073974 A223927 Adjacent sequences:  A034716 A034717 A034718 * A034720 A034721 A034722 KEYWORD nonn AUTHOR STATUS approved

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

Last modified April 21 14:09 EDT 2021. Contains 343154 sequences. (Running on oeis4.)