A4

n. international standard size for sheet of paper which is 21cm by 29.7cm (8.3 x11.7 inches)

A4 may mean:A4 paper size, an international standard paper size (210×297 mm) defined by  ISO 216Audi A4, a brand of carHMS A4, an A-class submarine of the Royal NavyLNER Class A4, a class of steam locomotives, including the famous MallardSouthern Winds, the Argentine airline, as its IATA codeV-2 rocket, as the actual model number for the German weaponIn town and country planning in the UK, A4 is the code for permission to use specific land or premises for pubs and bars.The UK Joint Force Air Component Headquarters - A4 Air Logistics branchA4, the New Jersey rock band.
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A4, paper that is a standard European size of 21 centimetres by 29.7 centimetres

This X-11 table is only available (applicable) when prior trading-day adjustment factors and a multiplicative model were specified. The user may specify a weight for each day (Monday through Friday); those weights are then proportionately adjusted so that they add to 7. The series (A 1 or A 3 ) is then divided by monthly calendar factors that are computed based on the number of the respective days in the respective month. Note that by default, the calendar factors are also adjusted for different lengths of different months; however, the length of month variability can also be included in the calendar factors (in which case a constant length of month of 30.4375 is used).
For more information, see X-11 Census Method II Seasonal Adjustment .

Pinyin: a1, a2, a3, a4, a
Wade-Giles: a1, a2, a3, a4, a
Zhuyin:
Hanzi:
(#677)

Pinyin: a1, a4, e1
Wade-Giles: a1, a4, e1
Zhuyin:
Hanzi:
(#622)