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A302495 a(n) is the least k such that k * A005277(n) is a term of A002202. 0

%I #50 Aug 04 2018 14:47:24

%S 2,2,3,5,2,5,2,2,3,2,2,3,2,2,6,3,3,2,4,2,3,3,2,6,2,3,2,3,2,3,3,3,5,2,

%T 2,3,3,3,2,3,2,4,6,3,2,2,3,2,4,3,3,2,5,2,3,2,7,2,3,2,2,3,3,4,3,3,2,2,

%U 9,2,4,2,2,2,3,2,5,2,2,3,5,6,2,12,6,2,3,3,3,3,2,3,3,2,3,2,5,3,2,3

%N a(n) is the least k such that k * A005277(n) is a term of A002202.

%C This sequence maps non-totients to totients, a(n) * A005277(n) is not a term of A005277, rather it is a term of A002202.

%C Conjecture: Every k > 1 eventually appears in the sequence.

%F a(n) = A067005(A005277(n)). - _Michel Marcus_, Jul 25 2018

%e a(1) = 2 because 2*A005277(1) = 2*14 = 28 is not a term of A005277.

%e a(3) = 3 because 3*A005277(3) = 3*34 = 102 is not a term of A005277.

%o (PARI) lista(nn) = {forstep(n=2, nn, 2, if (! istotient(n), my(k = 1); while (! istotient(k*n), k++); print1(k, ", ");););} \\ _Michel Marcus_, Jul 19 2018

%Y Cf. A000010, A002202, A005277, A000027.

%K nonn

%O 1,1

%A _Torlach Rush_, Jun 10 2018

%E More terms from _Michel Marcus_, Jul 19 2018

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