75210

Appears in sequences

• Treated as strings, phi(n) is a substring of sigma(n).at n=33A074452
• a(n) is the number of binary strings of length n such that no subsequence of length 5 or less contains 4 or more ones.at n=17A125513
• Numbers n such that sigma(n) = 10*phi(n) (where sigma=A000203, phi=A000010).at n=14A171256