Abstract: Methods and systems to surface, display and/or otherwise present items for sale that satisfy purchasing constraints are described In some example embodiments, the methods and systems access information associated with a purchasing constraint to buy items via an online retail site, determine and/or select items that satisfy the purchasing constraint, such as via information contained by a logistics table, and surface the identified items based on the determination. For example, the methods and systems ma display items available for purchase that satisfy the purchasing constraint via listing of items that satisfy a search query, among other things.

Abstract: A method and a system generate a contextual visual challenge image to be presented to a user thereby to verify that the user is human. For example, an image module generates a visual challenge to be presented to a user as part of a challenge-response to verify that the user is human. A contextual background module identifies a contextual background that is contextual to a specific environment and a combiner image module combines the visual challenge and the contextual background into an image which is to be presented to the user in the specific environment, the contextual background associating the visual challenge with the specific environment.

Abstract: Systems and processes for compressing a plurality of integers are provided. The plurality of integers is accessed. Each integer in the plurality of integers references an address in a record in a plurality of records stored in computer readable memory. The plurality of plurality of integers is fit to a fitting function having a plurality of coefficients thereby establishing a value for each coefficient. A lookup table is built. The table comprises, for each of the integers, other than the first and last integer, a residual that remains when a value of the fitting function is removed from the value of the integer. A representation of the fitting function, the value for each of the one or more coefficients, and the lookup table, are stored, thereby compressing the plurality of integers.