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

1,1

Links

Table of n, a(n) for n=1..45.

Example

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.

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 *)

Prog

(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

Crossrefs

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

Sequence in context: A179168 A259584 A184069 * A097231 A203251 A238924

Adjacent sequences: A096922 A096923 A096924 * A096926 A096927 A096928

Keyword

nonn,base

Author

Klaus Brockhaus, Jul 15 2004

Status

approved