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%I #10 May 13 2013 01:54:06
%S 1,4,16,18,64,72,256,288,405,486,726,847,1024,1125,1152,1183,1620,
%T 1734,1944,2166,2646,2904,3174,3388,4096,4500,4608,4732,5766,6480,
%U 6534,6727,6936,7776,8664,10584,11616,12250,12696,13552,14406,16384,16807,18000
%N Numbers n such that the digital binary sum of n equals core(n), the squarefree part of n.
%H Charles R Greathouse IV, <a href="/A077476/b077476.txt">Table of n, a(n) for n = 1..10000</a>
%e 486 = 2*3^5 hence the squarefree part of 486 is 2*3=6 and the binary representation of 486 is 111100110_2 with 6 1's, hence 486 is in the sequence.
%o (PARI) is(n)=my(h=hammingweight(n),t=n/h); denominator(t)==1 && issquare(t) && issquarefree(h) \\ _Charles R Greathouse IV_, Mar 29 2013
%K base,nonn
%O 1,2
%A _Benoit Cloitre_, Dec 01 2002