login
This site is supported by donations to The OEIS Foundation.

 

Logo


Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A066769 Sum_{d|n} d*fibonacci(n/d). 1
1, 3, 5, 9, 10, 21, 20, 39, 49, 80, 100, 195, 246, 424, 650, 1065, 1614, 2715, 4200, 6940, 11020, 17922, 28680, 46821, 75075, 121898, 196565, 318680, 514258, 833560, 1346300, 2180439, 3524900, 5706132, 9227600, 14936241, 24157854, 39096588 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

Dirichlet convolution of f(n)=n with the Fibonacci numbers F(n)=A000045. See the Apostol reference for Dirichlet convolutions. - Wolfdieter Lang, Sep 09 2008

REFERENCES

T. M. Apostol, Introduction to Analytic Number Theory, Springer-Verlag, 1976, pp. 29 ff.

LINKS

Robert Israel, Table of n, a(n) for n = 1..4740

FORMULA

G.f.: Sum_{i>0} i*x^i/(1-x^i-x^(2*i)). - Vladeta Jovovic, Oct 06 2003

MAPLE

N:= 100:

A:= Vector(N):

for k from 1 to N do

  f:= combinat:-fibonacci(k);

  ds:= [$1..floor(N/k)];

  A[k*ds] := A[k*ds] + f*Vector(ds);

od:

convert(A, list); # Robert Israel, Feb 08 2016

CROSSREFS

Cf. A000045, A007435.

Sequence in context: A286065 A063038 A236309 * A270780 A088607 A162699

Adjacent sequences:  A066766 A066767 A066768 * A066770 A066771 A066772

KEYWORD

easy,nonn

AUTHOR

Vladeta Jovovic, Jan 17 2002

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 | More pages
The OEIS Community | Maintained by The OEIS Foundation Inc.

License Agreements, Terms of Use, Privacy Policy .

Last modified September 25 21:33 EDT 2017. Contains 292500 sequences.