A095289 a(n) = the smallest number (in base 10) such that the product of its digits is >= n.

1, 2, 3, 4, 5, 6, 7, 8, 9, 25, 26, 26, 27, 27, 28, 28, 29, 29, 37, 37, 37, 38, 38, 38, 39, 39, 39, 47, 48, 48, 48, 48, 49, 49, 49, 49, 58, 58, 58, 58, 59, 59, 59, 59, 59, 68, 68, 68, 69, 69, 69, 69, 69, 69, 78, 78, 79, 79, 79, 79, 79, 79, 79, 88, 89, 89, 89, 89, 89, 89, 89, 89

Offset

1,2

Comments

This seems to be a nondecreasing sequence, at least to 10^5. - Robert G. Wilson v, Jul 05 2004

References

ARML 2002, Team event, Question 1.

Links

Table of n, a(n) for n=1..72.

Example

a(13) = 27 because 2*7 = 14 >= 13 and no number smaller than 27 has this property.

Mathematica

f[n_] := Block[{k = n}, While[Times @@ IntegerDigits[k] < n, k++ ]; k]; Table[ f[n], {n, 75}] (* Robert G. Wilson v, Jul 05 2004 *)
Module[{nn=100, pd}, pd=Table[{n, Times@@IntegerDigits[n]}, {n, nn}]; Table[SelectFirst[pd, #[[2]]>= k&], {k, 80}]][[;; , 1]] (* Harvey P. Dale, Jul 25 2023 *)

Crossrefs

Cf. A007954, A095706.

Sequence in context: A347189 A068189 A069716 * A174141 A343403 A095706

Adjacent sequences: A095286 A095287 A095288 * A095290 A095291 A095292

Keyword

base,easy,nonn

Author

Sam Handler (sam_5_5_5_0(AT)yahoo.com), Jul 02 2004

Extensions

More terms from Robert G. Wilson v, Jul 05 2004

Status

approved