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!)
A328878 If n = Product (p_j^k_j) then a(n) = Product (prime(p_j)). 1
1, 3, 5, 3, 11, 15, 17, 3, 5, 33, 31, 15, 41, 51, 55, 3, 59, 15, 67, 33, 85, 93, 83, 15, 11, 123, 5, 51, 109, 165, 127, 3, 155, 177, 187, 15, 157, 201, 205, 33, 179, 255, 191, 93, 55, 249, 211, 15, 17, 33, 295, 123, 241, 15, 341, 51, 335, 327, 277, 165, 283, 381, 85, 3, 451 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,2
LINKS
EXAMPLE
a(54) = 15 because 54 = 2 * 3^3 = prime(1) * prime(2)^3 and prime(prime(1)) * prime(prime(2)) = 3 * 5 = 15.
MATHEMATICA
a[n_] := Times @@ (Prime[#[[1]]] & /@ FactorInteger[n]); Table[a[n], {n, 1, 65}]
PROG
(PARI) a(n)={my(f=factor(n)[, 1]); prod(i=1, #f, prime(f[i]))} \\ Andrew Howroyd, Oct 29 2019
CROSSREFS
Sequence in context: A351368 A105445 A345014 * A178095 A177904 A049072
KEYWORD
nonn,mult
AUTHOR
Ilya Gutkovskiy, Oct 29 2019
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 April 29 18:29 EDT 2024. Contains 372114 sequences. (Running on oeis4.)