66947

Properties

Appears in sequences

• Number of Fibonacci numbers F(k), k <= 10^n, whose initial digit is 6.at n=5A073562
• Primes p such that p+2, p*(p+2)+18 and p*(p+2)+20 are also prime.at n=10A130737
• A122890 + A000012 - I, I = Identity matrix.at n=53A135723
• Final prime of first member of A019518 that is divisible by 19^n.at n=2A185668
• Primes p such that p^4 + p +/- 1 are twin primes.at n=28A236951
• Primes p such that 2*p^3 + 1 and 2*p^3 + 3 are also primes.at n=35A252042
• a(n) is the number of consecutive even prime gap pairs (g1, g2) satisfying g1 == 0 (mod 6) and g2 == 4 (mod 6) out of the first 2^n consecutive even prime gap pairs.at n=19A345334
• Prime numbersat n=6671