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A199987
Numbers with digital product = 4.
3
4, 14, 22, 41, 114, 122, 141, 212, 221, 411, 1114, 1122, 1141, 1212, 1221, 1411, 2112, 2121, 2211, 4111, 11114, 11122, 11141, 11212, 11221, 11411, 12112, 12121, 12211, 14111, 21112, 21121, 21211, 22111, 41111, 111114, 111122, 111141, 111212, 111221, 111411
OFFSET
1,1
COMMENTS
Subsequence of A034051.
LINKS
MAPLE
f:= proc(d) local b, i, t;
b:= (10^d-1)/9;
op(sort([seq(b+3*10^i, i=0..d-1),
seq(b+10^t[1]+10^t[2], t=combinat:-choose([$0..d-1], 2))]))
end proc:
seq(f(d), d=1..6); # Robert Israel, Jan 13 2021
MATHEMATICA
Select[Range[200000], Times @@ IntegerDigits[#] == 4 &] (* T. D. Noe, Nov 16 2011 *)
CROSSREFS
Sequence in context: A044437 A298008 A279414 * A201016 A317734 A154046
KEYWORD
nonn,base
AUTHOR
Jaroslav Krizek, Nov 13 2011
STATUS
approved