We gave away many of these postcards at the 2015 Joint Mathematics 
Meetings in San Antonio Texas in January 2015.

The text we printed on the reverse side of the postcard was the following
(at the top left). The numbers are the A-numbers of the sequences on
the front of the postcard.

OEIS.org
On-Line Encyclopedia of Integer Sequences

A250001,  A250000,  A160860,
A250120,  A160239,  A227133,
A232467,  A230628,  A229037.

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