(UK politics, colloquial) Synonym of 11 Downing Street

plural of hyperperfect number

(mathematics, number theory) Any natural number n for which, for some positive integer k, n = 1 + k(σ(n) - n - 1), where σ(n) is the sum of the positive divisors of n.

plural of vehicle identification number

A squarefree integer with at least three prime factors which fall into the pattern p_x=ap_x-1+b, where a and b are some integer constants and x is the index number of each prime factor in the factorization, sorted from lowest to highest.

A number of the form xʸ+yˣ, where x and y are integers greater than 1.

plural of Zeisel number

plural of Leyland number

plural of Laws number

An alphanumeric code representing a general class of ballad.