OFFSET
5,1
COMMENTS
Construction rules: 1) a(n) < a(n+1) 2) if you pick any digit "d" of the sequence, the closest identical one is at exactly "d" digits from it (jumping to the right or to the left).
EXAMPLE
Pick the leftmost "5" and jump 5 digits (to the right): you'll land on another "5".
Pick the third "6" (visible in 63) and jump 6 digits (to the right): you'll land on another "6" (161). [Jumping again 6 digits from there to the right would send you on another "6" (286), which is allowed].
Pick the first "0" (300) and jump 0 digits (to the right): you'll move to the next digit, which is a "0".
Note that the rule (2) forbids integers like "323" because if you pick one of those 3's the *closest* copy is at a "1" jump -- and not at a "3" jump, which is mandatory.
CROSSREFS
KEYWORD
base,easy,nonn
AUTHOR
Eric Angelini, Jul 03 2005
STATUS
approved