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%I #12 Feb 16 2017 18:00:25
%S 1,4,6,4,10,6,14,8,9,10,22,12,26,14,15,16,34,18,38,20,21,22,46,24,25,
%T 26,27,28,58,30,62,32,33,34,35,36,74,38,39,40,82,42,86,44,45,46,94,48,
%U 49,50,51,52,106,54,55,56,57,58,118,60,122,62,63,64,65,66,134,68,69,70,142
%N a(n) = n unless n is a prime, in which case a(n) = 2n.
%H N. J. A. Sloane, <a href="/A143545/b143545.txt">Table of n, a(n) for n = 1..10000</a>
%F a(n) = n + A061397(n), where A061397 = (0, 2, 3, 0, 5, 0, 7,...).
%F Equals row sums of triangle A143544.
%F a(n)=A066560(n), n>1. [From _R. J. Mathar_, Sep 05 2008]
%e a(3) = 6 = 2*3 since 3 is prime.
%e a(4) = 4 since 4 is a nonprime.
%Y Cf. A066560, A143544, A061397.
%Y See A282028 for another version.
%K nonn
%O 1,2
%A _Gary W. Adamson_, Aug 23 2008
%E Extended beyond a(14) by _R. J. Mathar_, Sep 05 2008
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