Triskaidekaphobia is fear or avoidance of the number 13. It is also a reason for the fear of Friday the 13th, called paraskevidekatriaphobia or friggatriskaidekaphobia.
Elevator panel in a building in the United States, where floors proceed from 12 to 14
The Death card, number 13, from an 18th century Tarot deck
The exposed lift shaft of an apartment block under construction. The lift shaft has numbers marking the levels, but the 13th level is marked with a heart instead.
Alternate mission patch of STS-41C, with a 13 and a black cat, as it landed on April 13th, which was a Friday the 13th and this was the mission originally scheduled as STS-13.
Arnold Schoenberg or Schönberg was an Austrian-American composer, music theorist, painter, teacher, and writer. Among the first modernist composers to write music of dense motivic relations saturating the musical texture, he propounded concepts like developing variation, the emancipation of the dissonance, and the "unity of musical space".
Schoenberg in Los Angeles, c. 1948
Arnold Schönberg in Payerbach, 1903
Schönberg Family, a painting by Richard Gerstl, 1907
Arnold Schoenberg by Egon Schiele, 1917