OFFSET
1,1
LINKS
Robert Israel, Table of n, a(n) for n = 1..10000
EXAMPLE
a(3) = 25 is a term because A067439(25) = 83 is prime.
MAPLE
filter:= proc(n) local t, k;
isprime(add(`if`(igcd(n, k)=1, n mod k, 0), k=2..n-1))
end proc:
select(filter, [$1..1000]);
PROG
(PARI) isok(n) = isprime(sum(i=1, n-1, if(gcd(n, i)==1, n%i))); \\ Michel Marcus, Jan 18 2021
CROSSREFS
KEYWORD
nonn
AUTHOR
J. M. Bergot and Robert Israel, Jan 17 2021
STATUS
approved