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%I #11 May 02 2021 17:24:24
%S 7,29,31,59,61,113,127,227,229,233,239,241,251,449,457,461,463,467,
%T 479,487,491,499,503,509,907,911,919,929,937,941,947,953,967,971,977,
%U 983,991,997,1009,1013,1019,1021,1801,1811,1823,1831,1847,1861,1867,1871,1873
%N Primes whose binary expansion begins 111.
%H Alois P. Heinz, <a href="/A262285/b262285.txt">Table of n, a(n) for n = 1..20000</a>
%p lis:=[]; q:=7;
%p for i from 1 to 10 do for j from 1 to 2^i-1 do
%p if isprime(q*2^i+j) then lis:=[op(lis),q*2^i+j]; fi; od: od:
%p lis;
%t Select[FromDigits[#,2]&/@(Join[{1,1,1},#]&/@Flatten[Table[Tuples[{0,1},n],{n,0,8}],1]),PrimeQ] (* or *) Select[Prime[Range[ 3,350]],Take[ IntegerDigits[ #,2],3]=={1,1,1}&] (* _Harvey P. Dale_, May 02 2021 *)
%Y Primes whose binary expansion begins with binary expansion of 1, 2, 3, 4, 5, 6, 7: A000040, A080165, A080166, A262286, A262284, A262287, A262285.
%Y Suggested by A262350.
%Y Column k=7 of A262365.
%K nonn,base
%O 1,1
%A _N. J. A. Sloane_, Sep 19 2015
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