OFFSET
1,2
EXAMPLE
Take integer [41] in the sequence, for instance : ...22 23 31 33 [41] 52 54 55 56.
The digit "4", jumping 4 integers back, ends on [22] which has no "4"; jumping 4 digits to the right ends on [56] which, again, has no "4". The same can be said for "1" (left -> [33]; right ->[52])
CROSSREFS
KEYWORD
base,easy,nonn
AUTHOR
Eric Angelini, Feb 18 2005
STATUS
approved