Table of n, a(n) for n=0..19.
The 5th number in the sequence must be the 5th pentagonal (5-gonal) number which can be divided by 5, namely 210.
Sequence in context: A267596 A119904 A271828 * A183264 A176972 A117393
Adjacent sequences: A117666 A117667 A117668 * A117670 A117671 A117672
Luc Stevens (lms022(AT)yahoo.com), Apr 11 2006