Fibonacci sequence
From Tardis Wiki, the free Doctor Who reference
A Fibonacci sequence was a sequence of numbers that included 34, 55, and 89. (PROSE: Daisy Chain) The Twelfth Doctor identified 55 as the tenth Fibonacci number. (TV: Flatline)
According to Saul, daisies had petal numbers in line with the Fibonacci sequence. (PROSE: Daisy Chain)
When Sir Toby Kinsella received a bottle of malt laced with a hallucinogen, it caused him to recite the Febinacci sequence ad infinitum in order to keep himself occupied. (AUDIO: Artificial Intelligence)
