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A067044
Smallest positive k such that k*n contains only even digits.
2
2, 1, 2, 1, 4, 1, 4, 1, 32, 2, 2, 2, 2, 2, 4, 3, 4, 16, 12, 1, 2, 1, 2, 1, 8, 1, 18, 1, 14, 2, 2, 2, 2, 2, 8, 8, 6, 6, 12, 1, 2, 1, 2, 1, 64, 1, 6, 1, 14, 4, 4, 4, 8, 9, 4, 4, 4, 7, 14, 1, 4, 1, 14, 1, 4, 1, 4, 1, 12, 4, 4, 4, 28, 3, 8, 3, 6, 6, 34, 1, 6, 1, 8, 1, 8, 1, 24, 1, 32, 32, 22, 5, 22, 3
OFFSET
1,1
EXAMPLE
a(7)=4 as among the multiples of 7 i.e. 7,14,21,28 28 is the smallest multiple with only even digits and a(7)= 28/7 = 4.
MATHEMATICA
Table[k = n; While[Length[Intersection[{1, 3, 5, 7, 9}, IntegerDigits[k]]] > 0, k = k + n]; k/n, {n, 100}] (* T. D. Noe, Jun 03 2013 *)
sk[n_]:=Module[{k=1}, While[!AllTrue[IntegerDigits[k*n], EvenQ], k++]; k]; Array[sk, 100] (* The program uses the AllTrue function from Mathematica version 10 *) (* Harvey P. Dale, Mar 27 2015 *)
CROSSREFS
Cf. A061807.
Sequence in context: A287597 A238552 A257523 * A325677 A343411 A287477
KEYWORD
nonn,base,easy
AUTHOR
Amarnath Murthy, Dec 29 2001
EXTENSIONS
More terms from Eli McGowan (ejmcgowa(AT)mail.lakeheadu.ca), May 06 2002
Data corrected by Paul Tek, Jun 03 2013
STATUS
approved