83621

Properties

Appears in sequences

• Primes that remain prime through 4 iterations of function f(x) = 10x + 9.at n=18A023329
• Primes for which only three iterations of 'Prime plus its digit sum equals a prime' are possible.at n=18A048525
• Primes of the form 2n^2+14n+5.at n=34A154577
• Fibonacci with priority for primes: a(0)=0, a(1)=1, for n >= 2, a(n) = a(n-1) + a(k), where 0 < k <= n-2 is maximal index such that a(n-1) + a(k) is prime. If there is no such k, then a(n) = a(n-1) + a(n-2).at n=36A216231
• SanD-68 primes p: such that p+d is also prime and sum of digits A007953(p(p+d)) = d, with d = 68.at n=7A307474
• Primes which yield again a prime when the digits are taken according to the lexicographically first superpermutation of corresponding order and of minimal length.at n=47A332088
• Prime numbersat n=8162