OFFSET
1,1
COMMENTS
The sequence always increases.
LINKS
G. C. Greubel, Table of n, a(n) for n = 1..10000
FORMULA
EXAMPLE
p_3=5, phi(5^2)=phi(25)=20, therefore a(3)=23
MAPLE
a:= n-> nextprime(2*binomial(ithprime(n), 2)):
seq(a(n), n=1..44); # Alois P. Heinz, Mar 15 2023
MATHEMATICA
Prime[1+PrimePi[EulerPhi[Prime[Range[41]]^2]]] (* T. D. Noe, Nov 15 2006 *)
PROG
(PARI) forprime (p=2, 200, print1(nextprime(eulerphi(p^2))", "))
CROSSREFS
KEYWORD
nonn
AUTHOR
Jon Perry, Jan 15 2003
EXTENSIONS
Corrected by T. D. Noe, Nov 15 2006
STATUS
approved