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!)
A054608 a(n) = Sum_{d|9} phi(d)*n^(9/d). 2

%I #26 Jul 11 2021 07:26:49

%S 0,9,540,19755,262296,1953405,10078164,40354335,134218800,387422001,

%T 1000002060,2357950419,5159783880,10604503845,20661052356,38443366215,

%U 68719485024,118587886425,198359302140,322687711611,512000016120

%N a(n) = Sum_{d|9} phi(d)*n^(9/d).

%H Seiichi Manyama, <a href="/A054608/b054608.txt">Table of n, a(n) for n = 0..10000</a>

%H <a href="/index/Rec#order_10">Index entries for linear recurrences with constant coefficients</a>, signature (10,-45,120,-210,252,-210,120,-45,10,-1).

%F G.f.: 9*x*(x^8 + 50*x^7 + 1640*x^6 + 9774*x^5 + 17390*x^4 + 9774*x^3 + 1640*x^2 + 50*x + 1) / (x - 1)^10. - _Colin Barker_, Dec 21 2012

%F a(n) = n^9 + 2*n^3 + 6*n. - _Seiichi Manyama_, Jul 11 2021

%o (PARI) a(n) = n^9+2*n^3+6*n; \\ _Seiichi Manyama_, Jul 11 2021

%Y Row n=9 of A185651.

%K nonn,easy

%O 0,2

%A _N. J. A. Sloane_, Apr 16 2000

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 March 28 05:39 EDT 2024. Contains 371235 sequences. (Running on oeis4.)