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A334963
a(n) is the least positive multiple of n that has at most two distinct digits.
1
1122, 515, 1144, 525, 212, 535, 1188, 545, 110, 111, 112, 113, 114, 115, 116, 117, 118, 119, 600, 121, 122, 3444, 744, 500, 252, 889, 4224, 774, 10010, 131, 660, 133, 4422, 4455, 272, 411, 414, 556, 700, 141, 994, 858, 144, 3335, 292, 441, 444, 447, 300, 151, 2888
OFFSET
102,1
LINKS
FORMULA
a(n) <= A004290(n).
a(n) = n if n is in A031955. - Bernard Schott, May 17 2020
EXAMPLE
a(102) = 1122 as 1122 = 11*102 is the least multiple of 102 that has at most 2 distinct digits.
MATHEMATICA
a[n_] := Module[{k = n}, While[Length @ Select[DigitCount[k, 10], # > 0 &] > 2, k += n]; k]; Array[a, 51, 102] (* Amiram Eldar, May 21 2020 *)
PROG
(PARI) a(n) = for(i = 1, oo, if(#Set(digits(i*n))<3, return(i*n)))
CROSSREFS
KEYWORD
nonn,base,easy
AUTHOR
David A. Corneth, May 17 2020
STATUS
approved