The Postage Question

CLASS POSTAGE the Hires ? ® ?

The war lingers on, and despite assurances to the contrary from the Nixon Administration, there appear to be few hopes for lasting peace. Precipitous technological advances during the last generation have left the world on the brink of devastation. Geological studies record " many examples of species that have failed to survive because of inadaptability to environmental change, but only Homo Sa...

Cryptographic Postage Indicia

We apply cryptographic techniques to the problem of fraud in metered mail. We describe a mail system that combines off-the-shelf barcode technology, tamper-proof devices, and cryptography in a fully-integrated secure franking system. This system provides protection against: 1. Tampering with postage meters to fraudulently obtain extra postage; 2. Forging and copying of stamps; 3. Unauthorized u...

Radiology on postage stamps.

A Note on the Postage Stamp Problem

Let h, k be fixed positive integers, and let A be any set of positive integers. Let hA := {a1 + a2 + · · · + ar : ai ∈ A, r ≤ h} denote the set of all integers representable as a sum of no more than h elements of A, and let n(h, A) denote the largest integer n such that {1, 2, . . . , n} ⊆ hA. Let n(h, k) = maxA n(h, A), where the maximum is taken over all sets A with k elements. The purpose of...

Generalizations of the Postage Stamp Problem

The postage stamp problem and its variations are classical problems in elementary number theory. This problem involves finding the largest value that cannot be expressed as a nonnegative linear combination of two relatively prime integers m and p. It turns out that this value can be defined as a function of m and p. An original proof of this fact is the first major goal of this paper. Moreover,...