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A078833 Greatest prime contained as binary substring in binary representation of n>1, a(1)=1.

%I A078833 #13 May 01 2014 01:28:42
%S A078833 1,2,3,2,5,3,7,2,2,5,11,3,13,7,7,2,17,2,19,5,5,11,23,3,3,13,13,7,29,7,
%T A078833 31,2,2,17,17,2,37,19,19,5,41,5,43,11,13,23,47,3,17,3,19,13,53,13,23,
%U A078833 7,7,29,59,7,61,31,31,2,2,2,67,17,17,17,71,2,73,37,37,19,19,19,79,5,17
%N A078833 Greatest prime contained as binary substring in binary representation of n>1, a(1)=1.
%C A078833 a(n) = A039634(n) for n<=44, but a(45) = 13 <> 11 = A039634(45);
%C A078833 for n>1: a(n) = n iff n is prime.
%C A078833 a(n) = A225243(n, A078826(n)). - _Reinhard Zumkeller_, Aug 14 2013
%H A078833 Reinhard Zumkeller, <a href="/A078833/b078833.txt">Table of n, a(n) for n = 1..10000</a>
%e A078833 n=12 -> '1100' contains 2 binary substrings which are primes: '11' (11bb) and '10' (b11b); 3='11' is the greater one, therefore a(12)=3.
%o A078833 (Haskell)
%o A078833 a078833 = last . a225243_row  -- _Reinhard Zumkeller_, Aug 14 2013
%Y A078833 Cf. A078832, A078826, A078822, A007088, A006530.
%K A078833 nonn,base
%O A078833 1,2
%A A078833 _Reinhard Zumkeller_, Dec 08 2002