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A093798
a(n) is the largest number such that all of a(n)'s length-n substrings are distinct and divisible by 45.
1
0, 900, 99000, 9990000, 999900000, 99999000000, 9999990000000, 999999900000000, 99999999000000000, 5555555595555555550555555555, 9555555559505555555505055555555, 9955555555950055555555050055555555, 9995555555595000555555550500055555555
OFFSET
1,2
EXAMPLE
a(3) is 99000 because its length-3 substrings (990, 900, 000) are all distinct and divisible by 45 and there is no larger number with this property.
CROSSREFS
Cf. A093211, A093212, ..., A093299.
Sequence in context: A359383 A374245 A093230 * A093218 A093215 A252674
KEYWORD
base,nonn
AUTHOR
Hans Havermann, Mar 28 2004
EXTENSIONS
a(11)-a(13) from John Cerkan, Jan 09 2018
STATUS
approved