67996domain: NAppears in sequencesLeast number x such that x^n has n digits equal to k. Case k = 7.at n=34A285454G.f. A(x) satisfies: A(x) = Sum_{n>=0} (n+1) * x^n / (1 - x^(n+1)*A(x)).at n=9A340357Numbers k such that the sum of the numbers from 1 to k and that from 1 to k+1 share the same sum of divisors.at n=30A375819