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 A252794 Numbers m such that 9^m + m is a semiprime. 1
 1, 5, 68, 85, 86, 92, 136 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 COMMENTS a(8) > 435. - Carl Schildkraut, Aug 14 2015 LINKS EXAMPLE 1 is in this sequence because 9^1+1 = 2*5 is semiprime. 5 is in this sequence because 9^5+5 = 2*29527 and these two factors are prime. MATHEMATICA Select[Range[435], PrimeOmega[9^# + #]==2 &] PROG (MAGMA) IsSemiprime:=func; [m: m in [1..435] | IsSemiprime(s) where s is 9^m+m]; CROSSREFS Cf. similar sequences listed in A252788. Cf. A252662. Sequence in context: A207979 A129963 A115764 * A328359 A003361 A336433 Adjacent sequences:  A252791 A252792 A252793 * A252795 A252796 A252797 KEYWORD nonn,more AUTHOR Vincenzo Librandi, Dec 27 2014 EXTENSIONS a(4)-a(7) from Carl Schildkraut, Aug 14 2015 STATUS approved

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Last modified December 3 16:20 EST 2020. Contains 338906 sequences. (Running on oeis4.)