281771domain: NAppears in sequencesErroneous version of A087316.at n=5A081744a(n) = Sum_{k=1..n} prime(k)^prime(n-k+1).at n=5A087316Numbers k such that sigma(sigma(k)) is a Fibonacci number.at n=6A280545a(n) = Sum_{k=1..n} k^2 * tau(k)^2, where tau is A000005.at n=32A320897