Quarter farthing Quarter farthing The British quarter farthing (d) coin was a unit of currency equaling one sixteenth of a penny ( of a pound sterling). It was produced for circulation in Ceylon in various years between 1839 and 1853, with proof coins being produced in 1868. It is the smallest denomination of pound sterling coin ever minted. The coin is considered to be part of British coinage because it has no indication of what country it was minted for, being made in the same style as the contemporary half-farthing which was legal tender in Britain between 1842 and 1869. Before Decimal
Quarter period is given by The real quarter period can be expressed as a Lambert series involving the nome: Additional expansions and relations can be found on the page for elliptic integrals. Quarter period In mathematics, the quarter periods "K"("m") and i"K" ′("m") are special functions that appear in the theory of elliptic functions. The quarter periods "K" and i"K" ′ are given by and When "m" is a real number, 0 ≤ "m" ≤ 1, then both "K" and "K" ′ are real numbers. By convention, "K" is called the "real quarter period" and i"K" ′ is called the "imaginary quarter