What are the last three letters in this series?
S, L, S, A, P, A, L, B, L, H, M, R, T, M, M, M, M, L, S, ?, ?, ?
B, A, S. The letters are the first initials of the host cities for the Summer Olympics through the 20th century:
Saint Louis, London, Stockholm, Antwerp, Paris, Amsterdam, Los Angeles, Berlin, London, Helsinki, Melbourne, Rome, Tokyo, Mexico City, Munich, Montreal, Moscow, Los Angeles, Seoul, Barcelona, Atlanta, Sydney
Today's brain teaser courtesy of Braingle.com.