This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A139408 #2 Mar 30 2012 17:37:44 %S A139408 1,260,450,543,630,1164,2080,3534,3640,4525,5425,11176,13365,15407, %T A139408 18333,24056,24552,25064,25452,26352,30660,37324,45136,46160,46325, %U A139408 49321,51742,52080,54540,67122,76041,76151,80325,81060,81217,81532 %N A139408 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 A139408 phi(1111900875)=1!!*1!!*1!!*1!!*9!!*0!!*0!!*8!!*7!!*5!!, so 1111900875 is in the sequence. %Y A139408 Cf. A066457, A139182. %K A139408 base,easy,nonn,less %O A139408 1,2 %A A139408 _Farideh Firoozbakht_, Apr 19 2008