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%I #12 Jan 26 2023 12:40:27
%S 5,7,9,13,15,19,25,27,33,37,39,43,45,55,57,67,69,73,79,85,87,93,99,
%T 103,109,115,117,123,129,135,139,145,157,159,169,177,183,187,193,195,
%U 213,219,223,225,235,237,243,247,249,253,255,265,277,285,289,297,303
%N Odd numbers n such that 2*n-7 is a prime of the form 4*k+3.
%D M. Cerasoli, F. Eugeni and M. Protasi, Elementi di Matematica Discreta, Bologna 1988.
%D Emanuele Munarini and Norma Zagaglia Salvi, Matematica Discreta,UTET, CittaStudiEdizioni, Milano 1997.
%H Harvey P. Dale, <a href="/A089193/b089193.txt">Table of n, a(n) for n = 1..1000</a>
%F a(n) = A087915(n) + 5.
%t tn7Q[n_]:=Module[{c=2n-7},PrimeQ[c]&&Divisible[c-3,4]]; Select[Range[ 5,301,2],tn7Q] (* _Harvey P. Dale_, May 18 2021 *)
%Y Cf. A002145, A087915.
%K easy,nonn
%O 1,1
%A _Giovanni Teofilatto_, Dec 08 2003
%E Offset corrected by _Arkadiusz Wesolowski_, Aug 09 2011
%E Corrected and extended by _Harvey P. Dale_, May 18 2021
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