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%I #13 Jul 22 2019 04:38:10
%S 3,6,16,64,512,5824,92288,1659136,36495872,1021871104,30656104448,
%T 1103619690496,44144787464192,1854081073168384,85287729365024768,
%U 4434961926979649536,257227791764816003072,15433667505888952582144
%N Number of numbers either relatively prime to or divisors of primorial number(n).
%H Amiram Eldar, <a href="/A051271/b051271.txt">Table of n, a(n) for n = 1..350</a>
%F A000005(A002110(n)) + A000010(A002110(n)); complementary to A045763(A002110).
%e The 4th primorial (210) has 16 divisors and 48 coprimes, so a(4) = 16 + 48 = 64.
%t DivisorSigma[0,#]+EulerPhi[#]&/@Rest[FoldList[Times,1,Prime[Range[20]]]] (* _Harvey P. Dale_, Sep 19 2013 *)
%Y Cf. A000005, A000010, A002110, A045763, A051272.
%K nonn
%O 1,1
%A _Labos Elemer_
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