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Numbers having exactly three divisors that are also suffixes in binary representation.
5

%I #9 May 02 2014 00:24:47

%S 15,27,30,39,45,51,54,60,75,78,85,87,90,99,102,108,111,119,120,123,

%T 125,135,147,150,153,156,159,165,170,171,174,175,180,183,187,195,198,

%U 204,205,207,216,219,221,222,238,240,243,245,246,250,267,270,279,285,287

%N Numbers having exactly three divisors that are also suffixes in binary representation.

%C A080942(a(n))=3.

%H Reinhard Zumkeller, <a href="/A080946/b080946.txt">Table of n, a(n) for n = 1..10000</a>

%o (Haskell)

%o a080946 n = a080946_list !! (n-1)

%o a080946_list = filter ((== 3) . a080942) [1..]

%o -- _Reinhard Zumkeller_, Mar 27 2014

%Y Cf. A080943, A080945, A080947, A007088, A080940, A080941.

%K nonn,base

%O 1,1

%A _Reinhard Zumkeller_, Feb 25 2003