OFFSET
1,1
COMMENTS
The first two occurrences of a(4) = 1828 appear consecutively as 18281828.
EXAMPLE
a(2) = 18 because 18 is the first 2-digit number to repeat in the decimal expansion of e = 2.7(18)28(18)...
2 appears at positions 0 and 4.
18 appears at positions 2 and 6.
182 appears at positions 2 and 6.
1828 appears at positions 2 and 6.
98793 appears at positions 478 and 494.
987931 appears at positions 478 and 494.
4349076 appears at positions 170 and 2731.
...
CROSSREFS
KEYWORD
nonn,base,more
AUTHOR
Bobby Jacobs, Dec 20 2016
EXTENSIONS
a(8)-a(12) from Alois P. Heinz, Dec 21 2016
STATUS
approved