1041920domain: NAppears in sequencesa(n) = 2^(n-4)*n*(n+1)*(n^2+5*n-2).at n=10A058649a(n) = 2*a(n-1) + 6*a(n-2), a(0) = 0, a(1) = 1.at n=12A0830992^(n-3)n(9n^2-9n+4).at n=10A086604Least integer m > 0 with pi(m*n) = sigma(m+n), where pi(.) and sigma(.) are given by A000720 and A000203.at n=27A247604