55558

Appears in sequences

• Numbers having four 5's in base 10.at n=27A043512
• Numbers n such that 4*10^n + 8*R_n - 1 is prime, where R_n = 11...1 is the repunit (A002275) of length n.at n=13A102999
• Near-repdigit semiprimes with 5 as repeated digit.at n=31A105986
• Numbers k with digits 5 and 8 only.at n=31A284381
• Expansion of (Product_{k>0} theta_3(q^k)/theta_4(q^k))^(1/2), where theta_3() and theta_4() are the Jacobi theta functions.at n=21A320968