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Nonprimes of the form 24n+7.
7

%I #8 Sep 08 2022 08:45:32

%S 55,175,247,295,319,343,391,415,511,535,559,583,655,679,703,775,799,

%T 847,871,895,943,1015,1111,1135,1159,1183,1207,1255,1351,1375,1495,

%U 1519,1591,1615,1639,1687,1711,1735,1807,1855,1903,1927,1975,2023,2047,2071

%N Nonprimes of the form 24n+7.

%H Vincenzo Librandi, <a href="/A135657/b135657.txt">Table of n, a(n) for n = 1..1000</a>

%t a = {}; Do[If[PrimeQ[24n + 7],[null], AppendTo[a, 24n + 7]], {n, 0, 1000}]; a

%t Select[24 Range[100] + 7, ! PrimeQ@# &] (* _Vincenzo Librandi_, Mar 22 2014 *)

%o (Magma) [a: n in [0..100] | not IsPrime(a) where a is 24*n+7]; // _Vincenzo Librandi_, Mar 22 2014

%Y Cf. A107006, A124477.

%K nonn,easy

%O 1,1

%A _Artur Jasinski_, Nov 25 2007