∑(∞,n=1)(n^2-2n+3)/(n^4+n^2-6)

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∑(∞,n=1)(n^2-2n+3)/(n^4+n^2-6)∑(∞,n=1)(n^2-2n+3)/(n^4+n^2-6)∑(∞,n=1)(n^2-2n+3)/(n^4+n^2-6)a1=S1=1-2+

∑(∞,n=1)(n^2-2n+3)/(n^4+n^2-6)
∑(∞,n=1)(n^2-2n+3)/(n^4+n^2-6)

∑(∞,n=1)(n^2-2n+3)/(n^4+n^2-6)
a1=S1=1-2+3=2
Sn=n²-2n+3
Sn-1=(n-1)²-2(n-1)+3
an=Sn-Sn-1=n²-2n+3-(n-1)²+2(n-1)-3=2n-3
n=1时,2-3=-1,与a1=2矛盾,因此n=1时,a1=2
n≥2时,an=2n-3
数列通项公式为
an=2 n=1
2n-3 n≥2