522461

Appears in sequences

• Numbers k = p*q*r, with odd primes p < q < r, such that Sister Beiter's cyclotomic coefficient conjecture is false.at n=27A146961
• a(0)=0, a(1)=1, a(n) = min{5 a(k) + (5^(n-k)-1)/4, k=0..(n-1)} for n>=2.at n=33A259669