38660

Appears in sequences

• Indices of triple-safe primes: p=prime(n) is double-safe: q=(p-1)/2, r=(q-1)/2 and s=(r-1)/2 are all prime (and q is double-safe).at n=26A075134
• Smallest n-aspiring number. That is, a(n) = smallest k such that s^(n)(k) is perfect but s^(n-1)(k) is not, where s(k) is the sum of the aliquot parts of k and s^(i) means iterate s i times.at n=21A099771
• Numbers n such that (6^n-1)^2-2 is prime.at n=17A100901
• a(n) = Sum_{d|n} (n-d)^tau(n/d).at n=14A345274
• a(n) = Sum_{k=1..n} k^2 * floor(n/k)^2.at n=37A350123
• Number of ways to partition digits 0-9 into signed terms in decreasing absolute value order with sum n.at n=18A389952