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%I #4 Oct 01 2013 17:57:41
%S 1100101,100110001001011011101111,101001111111111111010001,
%T 101010010110001110101101,101010011000011011011111,
%U 101111101111000111100010101,110100100000010010110010101
%N Primes in A071998.
%C Conjecture: there is an infinity of primes in A071998.
%o (PARI) binofbin(n) = { c=0; for(x=0,n, b=binary(x); ln=length(b); z=Str(b[1]); for(j=2,ln, z=concat(Str(z),Str(b[j])); ); d = eval(z); b=binary(d); ln=length(b); z=Str(b[1]); for(j=2,ln, z=concat(Str(z),Str(b[j])); ); \ print1(z,",") if(isprime(eval(z)),print1(eval(z),","); c++) ); print(); print(c) }
%K base,nonn
%O 1,1
%A _Cino Hilliard_, Sep 08 2003