Geometric Sequence

A geometric sequence is a sequence , , 1, ..., such that each term is given by a multiple  of the previous one. Another equivalent definition is that a sequence is geometric iff it has a zero series bias. If the multiplier is , then the th term is given by

Taking  gives the simple special case

The Season 1 episode "Identity Crisis" (2005) of the television crime drama NUMB3RS mentions geometric progressions.