OFFSET
1,1
LINKS
Robert Israel, Table of n, a(n) for n = 1..10000
Mathematics Stack Exchange, A curious pattern on primes congruent to 1 mod 4
MAPLE
filter:= proc(q) local t, p;
if not isprime(q) then return false fi;
t:= op(op(1, GaussInt:-GIfactor(q)));
p:= [abs(Re(t)+Im(t)), abs(Re(t)-Im(t))];
not isprime(p[1]) and not isprime(p[2])
end proc:
select(filter, [seq(i, i=1..10000, 4)]);
MATHEMATICA
lst = {}; Do[If[PrimeQ[a^2 + b^2] && ! PrimeQ[a + b] && ! PrimeQ[a - b], AppendTo[lst, a^2 + b^2]], {a, 2, 67}, {b, a -1}]; Take[ Union@ lst, 50] (* Robert G. Wilson v, Jan 06 2016 *)
CROSSREFS
KEYWORD
nonn
AUTHOR
Robert Israel, Jan 06 2016
STATUS
approved