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Numbers n such that 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 #8 Dec 22 2014 14:55:09

%S 1,2,3,15,18432,75600,276531978240000,4810168001497883738112000,

%T 215788176336727572480000000,

%U 2178419737991700039289327133392896000000000000

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

%C All terms are of the form 2^i*3^j*5^k*7^l.

%e 18432 is in the sequence because 18432 = 1!!*8!!*4!!*3!!*2!!.

%t Do[h=IntegerDigits[n];l=Length[h];If[n==Product[h[[k]]!!, {k, l}], Print[n]], {n, 2000000000}]

%Y Cf. A097653, A097654, A097643, A102279.

%K base,nonn

%O 1,2

%A _Farideh Firoozbakht_, Sep 10 2004

%E More terms from _Farideh Firoozbakht_, Jan 08 2005