OFFSET
1,1
COMMENTS
For each prime p, the sequence includes all k*p^p for k such that gcd(k,p)=1. - T. D. Noe
The asymptotic density of this sequence is 1 - Product_{p prime} (1 - 1/p^p + 1/p^(p+1)) = 0.14682429539560371215... . - Amiram Eldar, Jun 25 2022
LINKS
Reinhard Zumkeller, Table of n, a(n) for n = 1..10000
FORMULA
A203908(a(n)) = 0. - Reinhard Zumkeller, Dec 24 2013
EXAMPLE
54 is included because 3^3, but not 3^4, divides 54.
MATHEMATICA
fQ[n_] := Union[ Table[ #[[1]] == #[[2]]] & /@ FactorInteger[n]][[ -1]] == True; Select[ Range[2, 375], fQ[ # ] &] (* Robert G. Wilson v, Dec 14 2004 *)
PROG
(Haskell)
a100717 n = a100717_list !! (n-1)
a100717_list = filter ((== 0) . a203908) [1..]
-- Reinhard Zumkeller, Dec 24 2013
CROSSREFS
KEYWORD
nonn
AUTHOR
Leroy Quet, Dec 10 2004
EXTENSIONS
More terms from T. D. Noe and Robert G. Wilson v, Dec 14 2004
STATUS
approved