progress wherein terms (numbers) increase or decrease by equal differences (e.g. by the difference 2 - 2, 4, 6, 8, 10 or 10, 8, 6, 4, 2)
ARITHMETICAL PROGRESSION
Meaning of ARITHMETICAL PROGRESSION in English
Explanatory English dictionary bed edition. Толковый словарь английского языка Редакция bed. 2012