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A199989 Numbers with digital product = 8. 2

%I #15 Jan 13 2021 17:59:09

%S 8,18,24,42,81,118,124,142,181,214,222,241,412,421,811,1118,1124,1142,

%T 1181,1214,1222,1241,1412,1421,1811,2114,2122,2141,2212,2221,2411,

%U 4112,4121,4211,8111,11118,11124,11142,11181,11214,11222,11241,11412,11421,11811

%N Numbers with digital product = 8.

%H Robert Israel, <a href="/A199989/b199989.txt">Table of n, a(n) for n = 1..10000</a>

%p f:= proc(d) local b,i,t;

%p b:= (10^d-1)/9;

%p op(sort([seq(b+7*10^i,i=0..d-1),seq(b+10^t[1]+3*10^t[2],t = combinat:-permute([$0..d-1],2)),seq(b+10^t[1]+10^t[2]+10^t[3],t=combinat:-choose([$0..d-1],3))]))

%p end proc:

%p seq(f(d),d=1..5); # _Robert Israel_, Jan 13 2021

%t Select[Range[20000], Times @@ IntegerDigits[#] == 8 &] (* _T. D. Noe_, Nov 16 2011 *)

%Y Subsequence of A034055.

%Y Cf. A007954.

%K nonn,base

%O 1,1

%A _Jaroslav Krizek_, Nov 13 2011

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Last modified June 9 02:17 EDT 2024. Contains 373227 sequences. (Running on oeis4.)