A nontrivial power is a^b where a,b are integers and b>1.
Table of n, a(n) for n=0..6.
a(2)=216 because there are 11 even powers not larger than 216 and 9 odd powers not larger than 216, and 9 - 7 = 2.
Sequence in context: A120822 A013065 A013096 * A116092 A085631 A074073
Adjacent sequences: A200726 A200727 A200728 * A200730 A200731 A200732
Graeme McRae, Nov 21 2011