732511domain: NAppears in sequencesAlternately append n-th prime to beginning or end of previous term.at n=4A053065a(n) = n^4 + n^3 + n^2.at n=29A100019Odd numbers k that have a divisor d such that sigma(d)*d is equal to k.at n=13A327599a(n) is the number whose base-(n+1) expansion equals the binary expansion of n.at n=27A356274