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This template computes the Gregorian serial day. This is the day number according to the proleptic Gregorian calendar, with 1-1-1 as number 1. It works for all years, and is exact for at least the years from -100,000,000,000 until 100,000,000,000. The input is in parameters 1, 2, 3 for the year, the month number and the day.

It is demonstrated on the page Help:Demo of function time.

It uses function #time after reducing the year number to one in the range of this function, and converts the result to compensate for this reduction.

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