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A097372
Numbers n such that n=(d_1+6)*(d_2+6)*...*(d_k+6) where d_1 d_2 ... d_k is the decimal expansion of n.
7
90, 840, 4320, 59400, 60480, 917280, 2419200, 34992000, 3714984000, 460522782720, 896168448000, 2194698240000, 39109522636800, 229419122688000, 239446056960000, 650997662515200, 3954407288832000, 182279345504256000, 883270791696384000, 275333274192936960000
OFFSET
1,1
LINKS
Hiroaki Yamanouchi and Max Alekseyev, Table of n, a(n) for n = 1..29 (contains all terms below 10^100)
EXAMPLE
90 is in the sequence because 90 = (9+6)*(0+6).
MATHEMATICA
Do[h=IntegerDigits[n]; l=Length[h]; If[n==Product[h[[k]]+6, {k, l}], Print[n]], {n, 130000000}]
CROSSREFS
KEYWORD
base,nonn
AUTHOR
Farideh Firoozbakht, Sep 21 2004
EXTENSIONS
More terms from Giovanni Resta, Jan 16 2006
a(19)-a(24) from Hiroaki Yamanouchi, Sep 08 2014
a(25)-a(29) from Max Alekseyev, Jan 25 2015
STATUS
approved