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Shifts left under transform T where Ta is phi DCONV a.
7

%I #12 Feb 05 2022 16:01:14

%S 1,1,2,4,7,11,17,23,33,43,58,68,97,109,138,168,211,227,298,316,401,

%T 459,537,559,723,771,892,988,1173,1201,1507,1537,1791,1947,2190,2324,

%U 2825,2861,3195,3437,3999,4039,4794,4836,5481,5971,6552,6598,7775

%N Shifts left under transform T where Ta is phi DCONV a.

%C Eigensequence of triangle A054523; i.e., multiplication by A054523 shifts the sequence to (1, 2, 4, ...). - _Gary W. Adamson_, Apr 26 2009

%F a(1) = 1; a(n+1) = Sum_{d|n} phi(n/d) * a(d). - _Ilya Gutkovskiy_, Feb 23 2020

%t a[1] = 1; a[n_] := a[n] = Sum[EulerPhi[(n-1)/d]*a[d], {d, Divisors[n-1]}]; Table[a[n], {n, 1, 100}] (* _Vaclav Kotesovec_, Feb 23 2020 *)

%Y Cf. A000010, A054523.

%K nonn,eigen

%O 1,3

%A _Christian G. Bower_