Texas Instruments 83CML/ILI/U Guidebook - Page 124

you must specify an initial

Page 124 highlights

Recursive Sequences In a recursive sequence, the nth term in the sequence is defined in relation to the previous term or the term that precedes the previous term, represented by u(nN1) and u(nN2). A recursive sequence may also be defined in relation to n, as in u(n)=u(nN1)+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(nMin) = 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(nN1), press y [u 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(nN1), 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(nN2), 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). 6-6 Sequence Graphing

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6-6
Sequence Graphing
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