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!)
A347159 Sum of cubes of distinct prime divisors of n that are <= sqrt(n). 1
0, 0, 0, 8, 0, 8, 0, 8, 27, 8, 0, 35, 0, 8, 27, 8, 0, 35, 0, 8, 27, 8, 0, 35, 125, 8, 27, 8, 0, 160, 0, 8, 27, 8, 125, 35, 0, 8, 27, 133, 0, 35, 0, 8, 152, 8, 0, 35, 343, 133, 27, 8, 0, 35, 125, 351, 27, 8, 0, 160, 0, 8, 370, 8, 125, 35, 0, 8, 27, 476, 0, 35, 0, 8, 152 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,4
LINKS
FORMULA
G.f.: Sum_{k>=1} prime(k)^3 * x^(prime(k)^2) / (1 - x^prime(k)).
MATHEMATICA
Table[DivisorSum[n, #^3 &, # <= Sqrt[n] && PrimeQ[#] &], {n, 1, 75}]
nmax = 75; CoefficientList[Series[Sum[Prime[k]^3 x^(Prime[k]^2)/(1 - x^Prime[k]), {k, 1, nmax}], {x, 0, nmax}], x] // Rest
CROSSREFS
Sequence in context: A010679 A347157 A186981 * A156744 A228438 A021557
KEYWORD
nonn
AUTHOR
Ilya Gutkovskiy, Aug 20 2021
STATUS
approved

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 03:28 EDT 2024. Contains 371235 sequences. (Running on oeis4.)