Types of Sequence
● Progression → sequence or series
● Increasing sequence → each term greater than the previous term
● Decreasing sequence → each term less than the previous term
● Arithmetic sequence → difference between one term and the next is always
the same
● Geometric sequence → ratio of one term to the next is always the same
● Periodic sequence → repeats itself at regular intervals (number of terms
before repeat is called period)
● Series
○ The sum of all terms in a sequence
○ Use Σ notation
Arithmetic Progressions
● Un = a + (n – 1)d
○ Un is the term you desire to find
○ a is the first term
○ n is the term number you want to find
○ d is the common difference between the terms
○ Formula for the sum to a certain number (ie the first n terms
summed together)
● This type of series diverges → S∞ = ± ∞