Search: id:A066263 Results 1-1 of 1 results found. %I A066263 %S A066263 5,6,7,9,10,11,12,13,17,19,20,23,28,31,32,40,43,61,64,79,92,101,104, %T A066263 127,128,148,167,191,199,313,347,356,596,692,701,1004,1228,1268 %N A066263 2^n+1 has just two distinct prime factors. %H A066263 Samuel S. Wagstaff, The Cunningham Project %t A066263 f[n_] := First[ Transpose[ FactorInteger[2^n + 1, FactorComplete -> True]]]; Select[ Range[100], Length[f[ # ]] == 2 & ] %Y A066263 Cf. A073936. %Y A066263 Sequence in context: A047575 A014097 A081407 this_sequence A089192 A132829 A096820 %Y A066263 Adjacent sequences: A066260 A066261 A066262 this_sequence A066264 A066265 A066266 %K A066263 nonn %O A066263 1,1 %A A066263 Benoit Cloitre (benoit7848c(AT)orange.fr), Dec 31 2001 %E A066263 Edited by Robert G. Wilson v (rgwv(AT)rgwv.com), Jan 03 2002 Search completed in 0.001 seconds