160834

Appears in sequences

• G.f. satisfies: A(x) = x + A(A(A(x))^2).at n=7A141371
• Numbers n such that sigma(n) = sigma(n - phi(n)), where sigma(n) is the sum of divisors of n and phi(n) is the Euler totient function of n.at n=3A228519
• Array read by downward antidiagonals: A(n,k) = A(n-1,k+1) + Sum_{j=0..k} A(n-1,j)*A(k-j,0) with A(0,k) = 1.at n=42A392095