OFFSET
1,2
COMMENTS
The most common factor is 11, which catches most of the trivial cases such as 5000 (which when concatenated with its digit sum yields 55000... 11 * 5000). See A101171 for the first sequence member which uses a new factor.
There are only a finite number of terms ending with a nonzero digit. See A101171 for the proof. [From Max Alekseyev, May 08 2009]
EXAMPLE
a(50)=1125 because the number formed by concatenating the digit sum of 1125 (9) with 1125 yields a number (91125) that 1125 evenly divides. 91125 / 1125 = 81.
CROSSREFS
KEYWORD
base,nonn
AUTHOR
Chuck Seggelin (seqfan(AT)plastereddragon.com), Dec 03 2004
STATUS
approved