OFFSET
1,3
COMMENTS
Possible last two digits of triangular numbers k*(k+1)/2 (leading zeros omitted).
All triangular numbers less than 100 belong to this sequence. The sequence is finite with 44 terms: a(44)=96 is the last term.
EXAMPLE
The last two digits of k*(k+1)/2 can be 00, 01, 03, 20, 91, etc., but not 02, 04, 12, 97, etc.
MATHEMATICA
Union[Table[Mod[n*(n + 1)/2, 100], {n, 1, 100}]]
CROSSREFS
KEYWORD
base,fini,full,nonn
AUTHOR
Shyam Sunder Gupta, Aug 30 2013
STATUS
approved