There are two automatic email servers for identifying sequences:
lookup 1 2 5 14 42 132 429         [no commas!]
for example (with no Subject line). Up to 30 sequences can be submitted at the same time.
The email reply will tell you any sequences in the OEIS (up to a limit of 50) that match your sequence.
If the word "lookup" does not appear in your message, you will be sent the help file for this server.
You can also retrieve sequences by A-number -- say
lookup A12
lookup A45
lookup A129
etc
(However, you can't have both sequence lookups and A-number lookups in the same email message.)
containing a line like
lookup 1 3 5 7 9 11 13 15 17 19 21 23 25 27 29 31
(with no Subject line). The program will try VERY hard to find an explanation. Only one request may be submitted at a time, and (since this program does some serious computing), only one request per user per hour please. If there is no lookup line you will receive the help file for Superseeker.