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%I #5 Jul 14 2012 11:32:32
%S 3,5,7,8,11,13,14,19,23,31,32,47,61
%N Numbers n which do not exceed the sum of the binary digits in all primes <= n.
%C The sequence A168161 is a subsequence of the primes in this sequence.
%F A168162 = { n | n <= A095375(pi(n)) }, where pi(n) = A000720(n).
%e There is no prime <= 1 and 2 has only nonzero binary digit, therefore these numbers are not in the sequence.
%e However, a(1)=3 has two binary digits, so the total number of these equal 3.
%e Then, 4 is larger than this, but the prime p=5 again adds 2 nonzero binary digits adding to a total of 5=a(2).
%e Then 6 is larger than this, but the prime p=7 adds 3 more nonzero bits for a total of 8, such that a(3)=7 and a(4)=8 don't exceed this.
%o (PARI) s=0; for(n=1,9999, isprime(n) && s+=norml2(binary(n)); n<=s & print1(n", "))
%K fini,full,nonn,base
%O 1,1
%A _M. F. Hasler_, Nov 22 2009
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