A074954 Least perfect power b^e such that b^e-n is also a perfect power, or 0 if no such perfect power exists.

9, 27, 4, 8, 9, 0, 8, 9, 25, 2197, 27, 16, 49, 0, 16, 25, 25, 27, 27, 36, 25, 49, 27, 25, 125, 27, 36, 32, 225, 6889, 32, 36, 49, 0, 36, 100, 64, 1369, 64, 49, 49, 0, 484, 125, 49, 289, 128, 49, 81, 0, 100, 196, 729, 81, 64, 64, 121, 0, 900, 64, 125, 0, 64, 100, 81, 0, 1156

Offset: 1

Author

Reinhard Zumkeller, Oct 10 2002

Keywords

• nonn

Comments

a(A074981) = 0.

Examples

			a(30) = 6889: 30 = 83^2 - 19^3.
		

Links

• Eric Weisstein's World of Mathematics, Perfect Power.

Crossrefs

Cf. A001597.