OFFSET
1,1
COMMENTS
Subsequence of A034051.
LINKS
Robert Israel, Table of n, a(n) for n = 1..10000
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
KEYWORD
nonn,base
AUTHOR
Jaroslav Krizek, Nov 13 2011
STATUS
approved