Pascal's Triangle for
Graduate Students
A guide to the binomial coefficients for those exploring the far
reaches of mathematics
While Pascal's Triangle itself might seem a quaint
presentation of ideas a graduate student has already mastered during a
successful undergraduate study program, there are still many secrets
held by the array and useful techniques in higher many fields of higher
mathematics that come back to use of the binomial coefficients time and
time again. Here are a few highlights of the information presented
on this website that may be of use to a graduate student.
Modern Algorithmic Methods: This page is
a brief summary of the book "A=B" by Petkovšek, Wilf and Zeilberger,
which is available online.
The modern methods for finding closed formulas for difficult
summations, including of course summations involving binomial
coefficients, can be of use to people studying fields as diverse as
differential equations and computer science.
Identities Page: This list
of identities involving the binomial coefficients, while not completely
exhaustive, does list many identities the graduate student may not be
aware of, including a long list of named identities, like Dixon's
Identity, Abel's Identity, the identities from Pascal's original
treatise, etc.; also, there are many of the relations between the
binomial coefficients and famous sets of numbers like the Fibonaci
sequence, the Stirling numbers of the First and
Second Kinds and the numbers found in Euler's
Triangle. Most of the identities that have proofs attached to
them are proofs of an elementary nature (some so elementary that only a
hint is given instead of a proof), but some of these proofs may not be
known to every grad student, and their relative simplicity often belies
their mathematical power.
Recent Research: This is
a list of papers published over the past few years whose proofs rely on
relations between the binomial coefficients. Knuth once wrote,
"There are so many relations present that when someone finds a new
identity, there aren't many people who get excited about it anymore,
except the discoverer!" While discovering of the secrets of
Pascal's Triangle may not be the forefront of math that it was in the
day of Pascal or Tartaglia or Newton, and it might not be
enough to secure you a job as it did Professor
Moriarity, people are still publishing their new insights into
Pascal's Triangle, and every grad student knows that publishing is still
the name of the game.