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A097655
Numbers n such that n = d_1!!*d_2!!*...*d_k!! where d_1 d_2 ... d_k is the decimal expansion of n.
6
1, 2, 3, 15, 18432, 75600, 276531978240000, 4810168001497883738112000, 215788176336727572480000000, 2178419737991700039289327133392896000000000000
OFFSET
1,2
COMMENTS
All terms are of the form 2^i*3^j*5^k*7^l.
EXAMPLE
18432 is in the sequence because 18432 = 1!!*8!!*4!!*3!!*2!!.
MATHEMATICA
Do[h=IntegerDigits[n]; l=Length[h]; If[n==Product[h[[k]]!!, {k, l}], Print[n]], {n, 2000000000}]
CROSSREFS
KEYWORD
base,nonn
AUTHOR
Farideh Firoozbakht, Sep 10 2004
EXTENSIONS
More terms from Farideh Firoozbakht, Jan 08 2005
STATUS
approved