From the Jargon file, version 4.2.2...

off-by-one error
n. [common] Exceedingly common error induced in many ways, such as by starting at 0 when you should have started at 1 or vice-versa, or by writing < N instead of <= N or vice-versa. Also applied to giving something to the person next to the one who should have gotten it.

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Patrick Eaton (patrick@[this_domain])
Last modified: February 14, 2010
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