Texas Instruments TI-83 Calculator User Manual


 
6-6 Sequence Graphing
8306SEQN.DOC TI-83 international English Bob Fedorisko Revised: 02/19/01 12:22 PM Printed: 02/19/01 1:36
PM Page 6 of 16
In a recursive sequence, the
n
th term in the sequence is
defined in relation to the previous term or the term that
precedes the previous term, represented by
u(
n
N
1)
and
u(
n
N
2)
. A recursive sequence may also be defined in
relation to
n
, as in u(
n
)=u(
n
N
1)+
n
.
For example, in the sequence below you cannot calculate
u(5) without first calculating u(1), u(2), u(3), and u(4).
Using an initial value u(
n
Min) = 1, the sequence above
returns
1, 2, 4, 8, 16, . . .
Tip:
On the TI
-
83, you must type each character of the terms. For
example, to enter
u(
n
N
1)
, press
y
[
u
]
£
¹
À
¤
.
Recursive sequences require an initial value or values,
since they reference undefined terms.
If each term in the sequence is defined in relation to the
previous term, as in
u(
n
N
1)
, you must specify an initial
value for the first term.
If each term in the sequence is defined in relation to the
term that precedes the previous term, as in
u(
n
N
2)
, you
must specify initial values for the first two terms. Enter
the initial values as a list enclosed in braces ({ }) with
commas separating the values.
The value of the first term is 0 and the value of the second
term is 1 for the sequence
u(
n
).
Recursive
Sequences