OFFSET
1,1
COMMENTS
From Bernard Schott, Dec 23 2020: (Start)
Except for a(2)=3, (3, 5) gives A339698(2) = 19, there is no other pair of twin primes (p, p+2) (p in A001359) that gives a prime number of the form p^2-p*q+q^2 = p^2+2p+4.
There are no consecutive cousin primes (p, p+4) (p in A029710) that gives a prime number of the form p^2-pq+q^2 = p^2+4p+16.
There are no consecutive primes with a gap of 8 (p, p+8) (p in A031926) that give a prime number of the form p^2-pq+q^2 = p^2+8p+64. (End)
LINKS
Robert Israel, Table of n, a(n) for n = 1..10000
MAPLE
q:= 2: count:= 0: R:= NULL:
while count < 100 do
p:= q; q:= nextprime(q);
if isprime(p^2-p*q+q^2) then
count:= count+1; R:= R, p;
fi
od:
R; # Robert Israel, Dec 24 2020
PROG
(PARI) forprime(p=1, 1e4, my(q=nextprime(p+1)); if(ispseudoprime(p^2-p*q+q^2), print1(p, ", ")));
CROSSREFS
KEYWORD
nonn
AUTHOR
Michel Marcus, Dec 23 2020
STATUS
approved