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Numbers n such that phi(n)=(d_1+d_2+...+d_k)*(d_1!+d_2!+...+d_k!) where d_1 d_2...d_k is the decimal expansion of n.
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%I #4 Mar 30 2012 17:37:43

%S 1,26422,344070,666666,2117108,5184824,22047849,27469743,55368399,

%T 59546748,87986556

%N Numbers n such that phi(n)=(d_1+d_2+...+d_k)*(d_1!+d_2!+...+d_k!) where d_1 d_2...d_k is the decimal expansion of n.

%e 666666 is in the sequence because

%e phi(666666)=(6+6+6+6+6+6)*(6!+6!+6!+6!+6!+6!).

%t Do[h = IntegerDigits[n]; l = Length[h]; If[EulerPhi[n] == Sum[h[[k]], {k, l}]*Sum[h[[k]]!, {k, l}], Print[n]], {n, 87986556}]

%Y Cf. A058265.

%K base,fini,full,nonn

%O 1,2

%A _Farideh Firoozbakht_, May 12 2005