Sequence A002313 is the sequence of primes p = a*a + b*b, starting 2,5,13,17,..., members p > 2 have p = 1 mod 4. In analogy to the definition of primorial primes use the primes of sequence A002313 to build the product, written here as cp#353+1 or cp#1609-1. If cp#n+1 or cp#n-1 is prime, then n is in the sequence. Using +1 or -1 to define the type of prime cp#n+-1 we get the sequence 1,1,1,1,-1,1,...

A094249

Sequence A002313 is the sequence of primes p = a*a + b*b, starting 2,5,13,17,..., members p > 2 have p = 1 mod 4. In analogy to the definition of primorial primes use the primes of sequence A002313 to build the product, written here as cp#353+1 or cp#1609-1. If cp#n+1 or cp#n-1 is prime, then n is in the sequence. Using +1 or -1 to define the type of prime cp#n+-1 we get the sequence 1,1,1,1,-1,1,...