27181

Appears in sequences

• Numbers with three distinct prime factors which when concatenated in any order form prime numbers.at n=1A180679
• Numbers with three distinct prime factors (each of which may or may not be repeated) which when concatenated in any order form a prime number.at n=2A181559
• Number of primes of the form x^8 + 1 less than 10^n.at n=48A214454
• Let S be the binary string consisting of the first n digits of (100101)*; a(n) = number of ways of writing S as a product of palindromes.at n=26A215255
• Numbers with 3 or more prime factors (with multiplicity) such that every concatenation of their prime factors is prime.at n=31A217264
• G.f.: [ Sum_{n>=0} (4*n)!/(n!)^4 * x^(4*n)/(1-x)^(4*n+4) ]^(1/4).at n=10A262012