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A098114
Numbers n such that n=(d_1+4)*(d_2+4)*...*(d_k+4) where d_1 d_2 ... d_k is the decimal expansion of n.
5
120, 315, 4752, 7744, 24960, 57915, 3386880
OFFSET
1,1
COMMENTS
Suppose that m is in the sequence and A is set of the digits of m if 6, s times appears in A, then 10^s divides m, also if 1 is in A and at least one even number be in A then 10 divides m, etc.
No other terms below 10^100. - Max Alekseyev, Jan 25 2015
EXAMPLE
3386880 is in the sequence because
3386880=(3+4)*(3+4)*(8+4)*(6+4)*(8+4)*(8+4)*(0+4).
MATHEMATICA
Do[d=IntegerDigits[n]; k=Length[d]; If[n==Product[d[[j]]+4, {j, k}], Print[n]], {n, 1030000000}]
Select[Range[4000000], #==Times@@(IntegerDigits[#]+4)&] (* Harvey P. Dale, Dec 11 2012 *)
CROSSREFS
KEYWORD
base,more,nonn
AUTHOR
Farideh Firoozbakht, Sep 24 2004
STATUS
approved