| Definition. A sequence, unlike a set, is an
ordered, countable collection of values. Basically, a sequence is a function mapped
from the natural numbers to the real numbers. A sequence is denoted as {an}
= (an)n = (an) , where n is the nth
term in the sequence.
Ex. Here are some example sequences. By themselves they aren't
that interesting, but as always, there's more to study... The Harmonic
Sequence: (an)n = (1/n)n = ( 1, 1/2, 1/3,
1/4, 1/5, ... ) Reciprocal Squares: (an)n = (1/(n2))n
= ( 1, 1/4, 1/9, 1/16, ... ) Geometric Sequence (an)n
= (a/(rn))n = ( a, a/r, a/r2, a/r3,
... ) I always thought it was important for a sequence to start at index
1, but apparently, the geometric sequence starts at 0. I'm sure others can
start at 2, or any number you want for that matter. |