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%I #16 Nov 20 2019 19:57:57
%S 104,3255,22935,983775,1025504,2200694,2619705,4163355,4447064,
%T 4695704,6372794,9718904,11903775,23992215,26879684,29357475,37239735,
%U 40588485,41207144,48615735,56424555,76466985,81591194,83864055,113664135,118018094,166758015
%N Numbers n such that tau(n) = tau(n+1) and phi(n) = phi(n+1).
%C Intersection of A001274 and A005237. [_Alex Ratushnyak_, Mar 27 2013]
%H Donovan Johnson, <a href="/A217773/b217773.txt">Table of n, a(n) for n = 1..402</a> (terms < 10^12)
%t Select[Range[100000000],DivisorSigma[0, #] == DivisorSigma[0, # + 1] && EulerPhi[#] == EulerPhi[# + 1] &]
%t Position[Partition[Table[{DivisorSigma[0,n],EulerPhi[n]},{n,1668*10^5}], 2,1], _?(#[[1]]==#[[2]]&),1,Heads->False]//Flatten (* _Harvey P. Dale_, Nov 20 2019 *)
%Y Cf. A001274, A005237.
%K nonn
%O 1,1
%A _Jayanta Basu_, Mar 24 2013
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