A096925 Numbers n for which there are exactly four k such that n = k + (product of nonzero digits of k).

116, 405, 430, 474, 530, 546, 642, 744, 774, 836, 854, 855, 930, 958, 1038, 1055, 1070, 1088, 1104, 1110, 1116, 1134, 1154, 1162, 1236, 1366, 1400, 1405, 1418, 1430, 1455, 1530, 1642, 1744, 1774, 1836, 1854, 1855, 1930, 1958, 2112, 2137, 2185, 2199, 2205

Offset: 1

Author

Klaus Brockhaus, Jul 15 2004

Keywords

• nonn
• base

Examples

			279, 345, 381 and 401 are the only four k such that k + (product of nonzero digits of k) = 405, hence 405 is a term.
		

Crossrefs

Cf. A063114, A096347, A096922 - A096924, A096926 - A096931.

Programs

Mathematica

Take[Select[Tally[Table[k+Times@@(IntegerDigits[k]/.(0->1)),{k,100000}]],#[[2]] == 4&][[All,1]]//Sort,50] (* Harvey P. Dale, Oct 12 2022 *)

PARI

{c=4;z=2210;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