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Sequence gives k numbers from A123041.
2

%I #8 Sep 12 2022 04:18:28

%S 1,3,2,6,4,3,9,2,8,6,7,4,5,12,3,4,10,9,7,2,8,1,6,14,4,5,7,5,3,2,12,5,

%T 3,3,2,10,8,10,11,5,4,9,4,2,9,3,5,2,4,7,2,3,5,4,11,4,5,16,6,9,2,7,4,4,

%U 6,2,8,3,2,15,2,8,4,10,4,8,15,14,4,2,1,1,2

%N Sequence gives k numbers from A123041.

%H Amiram Eldar, <a href="/A123042/b123042.txt">Table of n, a(n) for n = 1..4309</a>

%F a(n) = A034448(A123041(n))^2/(A000203(A123041(n))*A047994(A123041(n))). - _Amiram Eldar_, Sep 12 2022

%t f[p_, e_] := (p - 1)*(p^e + 1)^2/((p^e - 1)*(p^(e + 1) - 1)); s[1] = 1; s[n_] := Times @@ f @@@ FactorInteger[n]; Select[s /@ Range[10^5], IntegerQ] (* _Amiram Eldar_, Sep 12 2022 *)

%Y Cf. A000203, A034448, A047994, A123041.

%K nonn

%O 1,2

%A _Yasutoshi Kohmoto_, Sep 24 2006

%E More terms from _Amiram Eldar_, Sep 12 2022