279816

Appears in sequences

• a(n) = f(f(f(f(f(n))))), where f(n) is prime(n)-1.at n=21A141139
• a(n) = prime(prime(prime(prime(prime(prime(n)-1)-1)-1)-1)-1)-1, where prime(n) is the n-th prime.at n=8A141185
• Expansion of q^(-3/4) * eta(q^2)^2 * eta(q^20) / (eta(q)^2 * eta(q^4)) in powers of q.at n=40A146163
• Numbers k such that both the sum of the semiprime divisors of k and the sum of the prime divisors of k are squares.at n=32A227478