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A169817 n-th prime with both a prime number of 0's and a prime number of 1's in binary representation minus n-th semiprime with both a prime number of 0's and a prime number of 1's in their binary representation. 0

%I #6 Nov 21 2013 12:49:56

%S 8,9,16,19,54,77,72,71,82,72,64,66,74,79,64,63,72,77,78,93,86,88,95,

%T 102,209,218,246,245,240,258,281,278,285,304,323,238,182,187,162,142,

%U 155,136,135,124,130,139,142,138,142,134,148,166,167,174,176,168,177,174

%N n-th prime with both a prime number of 0's and a prime number of 1's in binary representation minus n-th semiprime with both a prime number of 0's and a prime number of 1's in their binary representation.

%F a(n)=A144214(n)-A178350(n).

%e a(1)=A144214(1)-A178350(1)=17-9=8.

%t pn0Q[n_]:=PrimeQ[DigitCount[n,2,1]]&&PrimeQ[DigitCount[n,2,0]]; nn=600;Module[{ps=Select[Prime[Range[nn]],pn0Q],sps=Select[Range[nn], PrimeOmega[#]==2&&pn0Q[#]&],minlen},minlen=Min[Length[ps], Length[ sps]];First[#]-Last[#]&/@Thread[{Take[ps,minlen],Take[sps,minlen]}]] (* _Harvey P. Dale_, May 07 2012 *)

%Y Cf. A014499, A035103, A178064, A178065.

%K nonn

%O 1,1

%A _Juri-Stepan Gerasimov_, May 25 2010

%E Corrected (96 replaced by 86, all numbers from a(27) on replaced) by _R. J. Mathar_, Jun 04 2010

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Last modified May 13 07:22 EDT 2024. Contains 372498 sequences. (Running on oeis4.)