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Search: id:A091296
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%I A091296
%S A091296 9,15,33,35,39,51,55,57,77,91,93,95,111,115,119,133,155,159,177,319,335,
%T A091296 339,355,371,377,391,393,395,511,515,517,519,533,535,537,551,553,559,
%U A091296 573,579,591,597,713,717,731,737,753,755,771,779,791,793,799,913,917
%N A091296 Semiprimes with odd digits.
%C A091296 Semiprimes with odd digits are more numerous than those with even digits, 
               cf. A108636.
%t A091296 Select[Range[1000], Plus@@Last/@FactorInteger[ # ]==2&&Union[OddQ/@IntegerDigits[ 
               # ]]=={True}&]
%t A091296 PrimeFactorExponentsAdded[n_] := Plus @@ Flatten[ Table[ #[[2]], {1}] 
               & /@ FactorInteger[n]]; Select[ Range[ 938], PrimeFactorExponentsAdded[ 
               # ] == 2 && Union[ OddQ /@ IntegerDigits[ # ]] == {True} &] (from 
               Robert G. Wilson v)
%Y A091296 Cf. A001358 (semiprimes), A108636.
%Y A091296 Sequence in context: A051246 A062016 A108637 this_sequence A107076 A155775 
               A111148
%Y A091296 Adjacent sequences: A091293 A091294 A091295 this_sequence A091297 A091298 
               A091299
%K A091296 easy,nonn,base
%O A091296 1,1
%A A091296 Zak Seidov (zakseidov(AT)yahoo.com), Feb 22 2004
%E A091296 Corrected and extended by Ray Chandler (rayjchandler(AT)sbcglobal.net) 
               and Robert G. Wilson v (rgwv(AT)rgwv.com), Feb 25 2004
%E A091296 Edited by N. J. A. Sloane (njas(AT)research.att.com), Apr 20 2007

    
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Last modified November 30 13:13 EST 2009. Contains 167758 sequences.


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