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Numbers n for which there are exactly nine k such that n = k + (product of nonzero digits of k).
7

%I #4 Sep 15 2019 13:42:38

%S 11014,100774,111014,412055,510142,511146,633296,931395,983025,

%T 1008305,1011125,1031414,1100774,1101642,1108305,1111014,1412055,

%U 1510142,1511146,1633296,1931395,1983025,2011125,2011305,2012725,2110145

%N Numbers n for which there are exactly nine k such that n = k + (product of nonzero digits of k).

%e 88486, 96454, 99073, 99154, 99316, 100594, 100654, 100718 and 100732 are the only nine k such that k + (product of nonzero digits of k) = 100774, hence 100774 is a term.

%t Select[Tally[Table[n+Times@@DeleteCases[IntegerDigits[n],0],{n, 2111000}]],#[[2]]==9&][[All,1]]//Sort (* _Harvey P. Dale_, Sep 15 2019 *)

%o (PARI) {c=9;z=2120000;v=vector(z);for(n=1,z+1,k=addpnd(n);if(k<=z,v[k]=v[k]+1));for(j=1,length(v),if(v[j]==c,print1(j,",")))} \\for function addpnd see A096922

%Y Cf. A063114, A096347, A096922 - A096929, A096931.

%K nonn,base

%O 1,1

%A _Klaus Brockhaus_, Jul 15 2004