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A337776 a(n) is the order of A337775(n) (as defined in that sequence).

%I A337776 #24 Oct 25 2020 22:52:30
%S A337776 0,1,2,2,3,3,4,2,4,4,4,3,5,3,5,5,5,5,5,5,4,4,6,6,6,4,6,6,3,6,3,6,7,6,
%T A337776 5,4,5,4,7,5,7,5,5,7,4,5,5,4,7,4,7,7,7,3,8,7,7,4,7,7,7,6,6,5,6,6,5,6,
%U A337776 6,6,8,8,6,6,4,6,8,6,6,8,6,6,6,5,5,8,8,5,6,6,8,8,5,5,8,4,5
%N A337776 a(n) is the order of A337775(n) (as defined in that sequence).
%D A337776 J.-M. De Koninck, Ces nombres qui nous fascinent, Entry 108, p. 38, Ellipses, Paris 2008.
%D A337776 J.-M. De Koninck & A. Mercier, 1001 Problèmes en Théorie Classique Des Nombres, Problème 745 ; pp 95; 317-8, Ellipses Paris 2004.
%H A337776 J.-M. De Koninck, <a href="https://www.jstor.org/stable/4145084">When the Totient Is the Product of the Squared Prime Divisors: Problem 10966</a>, Amer. Math. Monthly, 111 (2004), p. 536.
%F A337776 rad(A337775(n))^a(n) = phi(A337775(n)).
%F A337776 a(n) = log(phi(A337775(n))) / log(rad(A337775(n))). - _Andrew Howroyd_, Sep 21 2020
%t A337776 nn = 97;
%t A337776 Sar = Table[0, {nn}]; Sar[[1]] = 2;
%t A337776 (*It is a list oh the sequence A337775*)
%t A337776 OrdSar = Table[0, {nn}]; OrdSar[[1]] = 0;
%t A337776 (*It is a sequence A337776 - the orders of members in sequence A337775*) For[Index = 2, Index <= nn, Index++,
%t A337776   InitialPrime = Prime[Index];
%t A337776   InitialInteger = InitialPrime - 1;
%t A337776   InitialArray = FactorInteger[InitialInteger];
%t A337776   For[i = 1, i <= Length[InitialArray], i++,
%t A337776    CurrentArray =
%t A337776     FactorInteger[InitialArray[[-i, 1]] - 1] ~Join~ InitialArray;
%t A337776    InitialInterger =
%t A337776     Product[CurrentArray[[k, 1]] ^ CurrentArray[[k, 2]], {k, 1,
%t A337776       Length[CurrentArray]}];
%t A337776      InitialArray = FactorInteger[InitialInterger];
%t A337776    ];
%t A337776   InitialArray = InitialArray ~Join~ {{InitialPrime, 0}};
%t A337776   Ord = Max[InitialArray[[All, 2]]];
%t A337776   Lint = Product[
%t A337776     Power[InitialArray[[k, 1]], Ord - InitialArray[[k, 2]] + 1], {k,
%t A337776      1, Length[InitialArray]}];
%t A337776   radn = Product[InitialArray[[k, 1]], {k, 1, Length[InitialArray]}];
%t A337776   Sar[[Index]] = Lint;
%t A337776   OrdSar[[Index]] = Ord;
%t A337776   ];
%t A337776 Print["Sar=  ", Sar]
%t A337776 Print["OrdSar=  ", OrdSar]
%Y A337776 Cf. A000010 (phi), A000040 (prime), A007947 (rad), A337775.
%K A337776 nonn
%O A337776 1,3
%A A337776 _Vladislav Shubin_, Sep 20 2020