50856

Appears in sequences

• Numbers k such that the period of the continued fraction for sqrt(k) contains exactly 21 ones.at n=29A031789
• Numbers whose base-15 representation has exactly 5 runs.at n=5A043672
• Values of n for which pi_{4,3}(p_n) - pi_{4,1}(p_n) = -1, where p_n is the n-th prime and pi_{m,a}(x) is the number of primes <= x which are congruent to a (mod m).at n=25A051024
• Self-convolution of A006664, which is the number of irreducible systems of meanders.at n=7A168357