Question:  U.S. Bank Tower is one of the tallest buildings west of the Mississippi River, but is shorter than which LA building?
Sentence (from "U.S. Bank Tower (Los Angeles)"): Because local building codes required all high-rise buildings to have a helipad, it was known as the tallest building in the world with a roof-top heliport from its completion in 1989 to 2004 when Taipei 101 opened.
Relevant evidence: No