Russian, One (1, 21, 31, 41, 51, 61, 71, 81, 91, 101, …)

Russian, Few (2, 3, 4, 22, 23, 24, 32, 33, 34, 42, …)

Russian, Many (0, 5, 6, 7, 8, 9, 10, 11, 12, 13, …)

Plural formula: (n%10==1 && n%100!=11 ? 0 : n%10>=2 && n%10<=4 && (n%100<10 || n%100>=20) ? 1 : 2)