635712domain: NAppears in sequencesa(n) = product of all even numbers between n-th prime and (n+1)-st prime.at n=22A061216Exponential Riordan array (e^(mx),x*A000108(x)), m=2.at n=30A185947Numbers m such that the equation m = k*sigma(k) has more than one solution.at n=19A337873