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%I #26 Sep 15 2022 02:15:08
%S 3,7,23,191,409
%N Primes that are less than the square of their least positive primitive root.
%C Alternatively, primes such that the least positive primitive root is greater than the square root of p.
%C Next term is greater than 10^9.
%D References and links at A001918.
%e The least primitive root of 23 is 5; 5^2 is greater than 23, so 23 is in the sequence.
%e The least primitive root of 409 is 21; 21^2 = 441 is greater than 409, so 409 is in the sequence.
%e 41 is not in the sequence because its least primitive root is 6, and 6^2 < 41.
%t Select[Prime[Range[1000]], PrimitiveRoot[#]^2 > # &]
%o (PARI) /* the following assumes that znprimroot() returns the smallest primitive root */
%o forprime(p=2,10^9,my(g=znprimroot(p));if(lift(g)^2>p,print1(p,", "))); \\ _Joerg Arndt_, Sep 17 2015
%o (Python)
%o from itertools import islice, count
%o from sympy import prime, primitive_root
%o def A262264_gen(): # generator of terms
%o return filter(lambda p: p < primitive_root(p)**2,(prime(n) for n in count(1)))
%o A262264_list = list(islice(A262264_gen(),5)) # _Chai Wah Wu_, Sep 14 2022
%Y Cf. A001918 (least positive primitive root of n-th prime).
%K nonn,more
%O 1,1
%A _Dale Taylor_, Sep 17 2015
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