OFFSET
1,1
COMMENTS
All terms are == 1 mod 6, and == {7, 13} mod 30.
Subsequence of A246842.
LINKS
Zak Seidov, Table of n, a(n) for n = 1..1592
PROG
(PARI)
forprime(p=1, 10^12, c=0; for(i=1, 9, if(ispseudoprime(p+(2*i)^2), c++); if(!ispseudoprime(p+(2*i)^2), break)); if(c==9, print1(p, ", "))) \\ Derek Orr, Sep 11 2014
(PARI) is(n)=my(t=n%5); if(t!=2 && t!=3, return(0)); forstep(i=4, 18, 2, if(!isprime(n+i^2), return(0))); isprime(n) && isprime(n+4)
p=2; forprime(q=3, 1e12, if(q-p==4 && is(p), print1(p", ")); p=q) \\ Charles R Greathouse IV, Sep 11 2014
CROSSREFS
KEYWORD
nonn
AUTHOR
Zak Seidov, Sep 11 2014
STATUS
approved