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Maximally asymmetric odd primes in binary.
3

%I #16 Apr 23 2020 19:27:20

%S 3,5,7,11,13,19,23,29,43,53,71,79,83,101,109,113,151,179,233,241,271,

%T 311,331,347,397,421,457,599,683,739,797,853,937,977,1087,1103,1223,

%U 1307,1427,1459,1597,1613,1733,2017,2111,2143,2503,2731,3011

%N Maximally asymmetric odd primes in binary.

%C Primes p for which A037888(p) = floor((A070939(p)-2)/2). Those numbers contain just the first and last bits mirroring each other. Hence all the odd primes without leading zeros begin and end in 1 bits, the unique totally asymmetric prime being (10)_2 = 2.

%H A. Karttunen, J. Moyer: <a href="/A095062/a095062.c.txt">C-program for computing the initial terms of this sequence</a>

%e a(10)=(110101)2 since the symmetry is limited to the first and last bits. The number 47=(101111)2 is not a term because from left to right, the third bit matches with the fourth.

%o (PARI)A070939(p)={return(floor(log(p)/log(2))+1)};

%o A037888(p)={v=binary(p);s=0;j=#v;for(k=1,#v,s+=abs(v[k]-v[j]);j--);return(s/2);}; forprime(p=3,3011, if(A037888(p) ==floor((A070939(p)-2)/2),print1(p,", ")))

%Y Cf. A095757, A095749, A095748.

%K nonn,base

%O 1,1

%A _Antti Karttunen_, Jun 12 2004

%E Edited by _Washington Bomfim_, Jan 13 2011