2 added 61 characters in body edited Mar 20 '16 at 10:05 Oray 17.3k44 gold badges4141 silver badges176176 bronze badges First Series could be A006450 or A175247 (Primes with noncomposite subscripts.) In spite of the type of the series, the answer becomes 67. And the second one A007570 = $$F(F(n))$$ where F is a Fibonacci number. so the answer becomes 10946 And there is no relation that I have found between these. First Series could be A006450 or A175247 (Primes with noncomposite subscripts.) In spite of the type of the series, the answer becomes 67. And the second one A007570 = $$F(F(n))$$ where F is a Fibonacci number. so the answer becomes 10946 First Series could be A006450 or A175247 (Primes with noncomposite subscripts.) In spite of the type of the series, the answer becomes 67. And the second one A007570 = $$F(F(n))$$ where F is a Fibonacci number. so the answer becomes 10946 And there is no relation that I have found between these. 1 answered Mar 20 '16 at 10:01 Oray 17.3k44 gold badges4141 silver badges176176 bronze badges First Series could be A006450 or A175247 (Primes with noncomposite subscripts.) In spite of the type of the series, the answer becomes 67. And the second one A007570 = $$F(F(n))$$ where F is a Fibonacci number. so the answer becomes 10946