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%I #19 Sep 08 2022 08:46:16
%S 3,5,2,3,11,5,15,7,19,21,23,11,27,13,31,33,35,17,39,19,43,45,47,23,51,
%T 53,55,57,59,29,63,31,67,69,71,73,75,37,79,81,83,41,87,43,91,93,95,47,
%U 99,101,103,105,107,53,111,113,115,117,119,59,123,61,127
%N a(n) = n if n is prime, a(n) = 2*n+3 otherwise.
%C Prime numbers repeated: 3, 5, 11, 19, 23, 31, 43, 47, 53, 59, 67, 71, ..., that is A065091 without A089531.
%H Vincenzo Librandi, <a href="/A272476/b272476.txt">Table of n, a(n) for n = 0..1000</a>
%t Table[If[PrimeQ[n], n, 2 n + 3], {n, 0, 150}]
%o (Magma) [IsPrime(n) select n else 2*n+3: n in [0..80]];
%Y Cf. A000040, A018252.
%Y Cf. A061397, A191558.
%K nonn,easy
%O 0,1
%A _Vincenzo Librandi_, May 02 2016
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