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Numbers n such that phi(n)=d_1!!*d_2!!*...*d_k!! where d_1 d_2 ... d_k is the decimal expansion of n.
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%I #2 Mar 30 2012 17:37:44

%S 1,260,450,543,630,1164,2080,3534,3640,4525,5425,11176,13365,15407,

%T 18333,24056,24552,25064,25452,26352,30660,37324,45136,46160,46325,

%U 49321,51742,52080,54540,67122,76041,76151,80325,81060,81217,81532

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

%e phi(1111900875)=1!!*1!!*1!!*1!!*9!!*0!!*0!!*8!!*7!!*5!!, so 1111900875 is in the sequence.

%Y Cf. A066457, A139182.

%K base,easy,nonn,less

%O 1,2

%A _Farideh Firoozbakht_, Apr 19 2008