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%I #11 Mar 03 2015 00:49:59
%S 0,1,1,3,3,5,1,3,7,13,15,5,9,11,15,21,27,29,3,7,9,15,19,25,33,37,39,
%T 43,45,49,63,3,9,11,21,23,29,35,39,45,51,53,63,65,69,71,83,95,99,101,
%U 105,111,113,123,1,7,13,15,21,25,27,37,51,55,57,61,75,81,91,93,97,103
%N Change the first bit to 0 in binary notation for the n-th prime.
%C a(n) = A053645(A000040(n)).
%H Harvey P. Dale, <a href="/A091931/b091931.txt">Table of n, a(n) for n = 1..1000</a>
%F a(n) = A000040(n) - 2^(A035100(n)-1).
%t FromDigits[Rest[IntegerDigits[#,2]],2]&/@Prime[Range[80]] (* _Harvey P. Dale_, Apr 20 2012 *)
%o (PARI) for(n=1,72,p=prime(n);p-=2^(#binary(p)-1);print1(p,", ")) \\ _Washington Bomfim_, Jan 18 2011
%Y Cf. A091932.
%K nonn,base,easy
%O 1,4
%A _Reinhard Zumkeller_, Feb 14 2004
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