History of the hamburger in the United States is found in Japan, but is a local variation. History of the hamburger in the United States A hamburger (or burger) is a sandwich that consists of a cooked ground meat patty, usually beef, placed between halves of a sliced bun or between slices of bread or toast. Hamburgers are often served with various condiments, such as mustard, mayonnaise, and ketchup, and other options including lettuce, tomato, onion, pickles, and cheese. The Texas historian Frank X. Tolbert attributes the invention of the hamburger to Fletcher Davis of Athens, Texas. Davis is believed to have sold hamburgers at his café at
Hamburger moment problem "Jacobi matrix representation". This in turn leads to a "tridiagonal model" of positive Hankel kernels. An explicit calculation of the Cayley transform of "T" shows the connection with what is called the "Nevanlinna class" of analytic functions on the left half plane. Passing to the non-commutative setting, this motivates "Krein's formula" which parametrizes the extensions of partial isometries. The cumulative distribution function and the probability density function can often be found by applying the inverse Laplace transform to the moment generating function provided that this function converges. Hamburger moment problem In mathematics, the Hamburger moment problem, named after Hans Ludwig