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coefficient of x into (1+x)(1-2x)(1+3x)(1-4x) ... (1-2008x) (HOMC 2008 J Q3)
coefficient of x into (1+x)(1-2x)(1+3x)(1-4x) ... (1-2008x) (HOMC 2008 J Q3)
Source:
July 25, 2019
polynomial
algebra
combinatorics
coefficient
Problem Statement
Find the coefficient of
x
x
x
in the expansion of
(
1
+
x
)
(
1
−
2
x
)
(
1
+
3
x
)
(
1
−
4
x
)
.
.
.
(
1
−
2008
x
)
(1 + x)(1 - 2x)(1 + 3x)(1 - 4x) ...(1 - 2008x)
(
1
+
x
)
(
1
−
2
x
)
(
1
+
3
x
)
(
1
−
4
x
)
...
(
1
−
2008
x
)
.
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