This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A161793 #7 Mar 11 2014 01:32:33 %S A161793 1,2,4,5,6,8,9,11,13,14,16,23,25,27,29,30,32,47,55,59,61,62,64,81,95, %T A161793 111,119,121,123,125,126,128,191,223,239,247,251,253,254,256,343,383, %U A161793 447,479,495,503,507,509,510,512,767,895,959,991,1007,1015,1019,1021 %N A161793 If b(n) is the number of 0's in the binary representation of n, then the positive integer n is included if n = k^b(n), for some k = integer. %e A161793 25 in binary is 11001, which has two 0's. Since 25 = 5^2, with an exponent of 2, then 25 is included in this sequence. %Y A161793 A161792 %K A161793 base,nonn %O A161793 1,2 %A A161793 _Leroy Quet_, Jun 19 2009 %E A161793 More terms from _Sean A. Irvine_, Mar 14 2010