OFFSET
1,3
COMMENTS
If n has no divisors among 2,3,5 or 7 then the only term with digit sum n is the repunit A002275(n) = 1111... n times.
CROSSREFS
KEYWORD
base,nonn
AUTHOR
Amarnath Murthy, May 12 2002
EXTENSIONS
Edited and extended by Ray Chandler, Feb 10 2009
STATUS
approved