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Problem 1002 >> Solve Me!
onetwogoo @ 2011-12-20 22:26:54
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找规律。
设数列{Ai}表示n为i时的答案,另定义数列{Bi}。其中
B1=1,B2=1
B3=4,B4=3
B5=11,B6=8
B7=29,B8=21
……
Bi=3*B(i-2)-B(i-4)

则当i为奇数时
Ai=Bi^2
当i为偶数时
Ai=5*Bi^2

高精递推计算Ai输出即可。
KotoriItsuka @ 2014-12-24 14:07:56
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挖坟求证明 > <
cnlarryzhong @ 2017-11-10 16:48:52
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谢谢
lin1043 @ 2017-12-31 19:01:57
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http://oeis.org/A004146 证明在这里
PS挖了一下坟……
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