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For example, given NBIT = 8, B(0) = 10
3
, τ
B
= 10 and t =
200, an average 10
3
/2
8
(1 + 200
.
In(2)/10) ~ 58 cells with
affi nity NBIT are created within 200 time steps. Let’s make
another example, NBIT = 12, B(0) = 10
3
, τ
B
= 10, t = 500; then,
on an average, 10
3
/2
12
(1 + 500
.
(In(2))/10) ~ 87 cells with a
perfect match are created in 500 time steps. That’s a small
number! Consider however that the probability that not
even a single perfect match string is created in t time steps is
(1 – p)
B(0)
(
1 + t
In(2)
τ
B
)
which in this example means that the probability to fall short
of a 12-bit perfect match in 200 time steps is 1.7
.
10
–4
. Note
that when ...