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%I A143231 #13 Sep 08 2018 21:18:27
%S A143231 1,2,8,12,40,24,108,88,168,128,420,184,696,384,576,640,1536,612,2160,
%T A143231 1024,1680,1500,3784,1440,4000,2544,4140,2904,7560,2224,9240,5184,
%U A143231 6880,5760,9216,4752,15552,8100,11376,7840,21200,6504,24528,12080,15072,14300
%N A143231 a(n) = A000010(n) * A002088(n).
%H A143231 Nathaniel Johnston, <a href="/A143231/b143231.txt">Table of n, a(n) for n = 1..2500</a>
%F A143231 a(n) = A000010(n) * A002088(n). Equals row sums of triangle A143230.
%e A143231 a(5) = 40 = A000010(5) * A002088(5) = 4 * 10.
%e A143231 a(5) = 40 = sum of row 5 terms of triangle A143230: (4 + 4 + 8 + 8 + 16).
%p A143231 with(numtheory):
%p A143231 a := proc(n) return phi(n)*add(phi(k),k=1..n): end:
%p A143231 seq(a(n),n=1..46); # _Nathaniel Johnston_, Jun 26 2011
%o A143231 (PARI) a(n)=sum(k=1, n, eulerphi(k))*eulerphi(n) \\ _Charles R Greathouse IV_, Feb 21 2013
%Y A143231 Cf. A000010, A002088, A143230.
%K A143231 nonn
%O A143231 1,2
%A A143231 _Gary W. Adamson_, Jul 31 2008
%E A143231 Terms after a(14) from _Nathaniel Johnston_, Jun 26 2011

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