(computing, databases) In the design of a database table, the primary key (abbreviated PK) is selected among the non-empty set of candidate keys. The PK is a column (or an irreducible group of columns) able to identify every row of the table.

(mathematics) Either of a pair of prime numbers that differ by two.

(mathematics) The factorization of a positive integer into its constituent prime numbers

(mathematics) Either of a pair of prime numbers that differ by six.

For sale at half the normal price.

For sale at half the normal price.

(mathematics) An ordered set of prime numbers having a constant difference between successive elements

(mathematics) Either of a pair of prime numbers that differ by four

(mathematics) The factorization of an integer into prime numbers.

(economics) A statistical estimate of the level of prices of goods and services bought for consumption purposes by households.