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%I #15 Mar 02 2018 22:44:41
%S 1,3,3,6,3,10,3,11,7,12,3,22,3,14,13,20,3,27,3,28,15,18,3,44,9,20,17,
%T 34,3,50,3,37,19,24,17,64,3,26,21,58,3,62,3,46,39,30,3,86,11,49,25,52,
%U 3,74,21,72,27,36,3,120,3,38,47,70,23,86,3,64,31,82,3,135,3,44,55,70,23,98,3
%N a(n) = sigma(n) + tau(n) - n.
%H Antti Karttunen, <a href="/A163163/b163163.txt">Table of n, a(n) for n = 1..65537</a>
%H Antti Karttunen, <a href="/A163163/a163163.png">Sequence plotted up to n=10000, showing the details better</a>
%F a(n) = A007503(n) - n = A000203(n) + A000005(n) - n.
%F a(n) = A000005(n) + A001065(n). - _Antti Karttunen_, Feb 25 2018
%e a(10) = A007503(10) - 10 = 22 - 10 = 12.
%t Table[Apply[Plus, DivisorSigma[#, n] & /@ {0, 1}] - n, {n, 79}] (* _Michael De Vlieger_, Feb 25 2018 *)
%o (PARI) A163163(n) = (sigma(n)+numdiv(n)-n); \\ _Antti Karttunen_, Feb 25 2018
%Y Cf. A000005, A000027, A000203, A001065, A007503.
%K nonn,easy
%O 1,2
%A _Juri-Stepan Gerasimov_, Jul 22 2009
%E 47 replaced with 37 by _R. J. Mathar_, Jul 25 2009
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