OFFSET
1,1
COMMENTS
LINKS
Jianing Song, Table of n, a(n) for n = 1..20000
EXAMPLE
a(12) = 35 since phi(35) = 24 is divisible by 2*12, and there is no m < 12 such that phi(m) is divisible by 2*12.
a(16) = 51 since phi(51) = 32 is divisible by 2*16, and there is no m < 16 such that phi(m) is divisible by 2*16.
PROG
(PARI) a(n) = for(m=1, (2*n)^2, if(eulerphi(m)%(2*n)==0, return(m)))
(Python)
from sympy import totient as phi
def a(n):
k = 1
while phi(k)%(2*n) != 0: k += 1
return k
print([a(n) for n in range(1, 61)]) # Michael S. Branicky, Feb 21 2021
CROSSREFS
KEYWORD
nonn
AUTHOR
Jianing Song, Feb 21 2021
STATUS
approved