%I A075308
%S A075308 4,8,28,84,242,744,2284,7096,22179,69561,218759,689206,2173942,6862783,
%T A075308 21676671,68493153,216477260,684309327,2163434093,6840212693,
%U A075308 21628140126,68388775913,216252650605,683825838922
%N A075308 Number of n-digit perfect powers.
%C A075308 Starting with n=2, a(n)=A070428(n) - A070428 (n-1). E.g. a(3)=28 = A070428(3) 
               - A070428 (2). = 41-13 ( in A070428 offset is 0).
%e A075308 a(2)=8 because there are 8 2-digit pp's: 16, 25, 27, 32, 36, 49, 64, 
               81.
%Y A075308 Cf. A001597, A070428.
%Y A075308 Sequence in context: A105723 A143555 A025234 this_sequence A020331 A082595 
               A080072
%Y A075308 Adjacent sequences: A075305 A075306 A075307 this_sequence A075309 A075310 
               A075311
%K A075308 easy,nonn,base
%O A075308 1,1
%A A075308 Zak Seidov (zakseidov(AT)yahoo.com), Oct 11 2002