[離散] (n+1)^2 (n+1)^3 ...
題目
For any a屬於Z n>=0 ， prove that n^7/7+n^3/3+11n/21 is an integer
我用數學歸納法證到
n時 n^7/7+n^3/3+11n/21
n+1時 (n+1)^7/7+n^3/3+11n/21+11/21+n^2+n+1/3+1/7
只解到３的部分
把(n+1)^7分解後 可以除７
n^7+7n^6+21n^5+35n^4+35n^3+21n^2+7n+1
想問板上的高手們
有個關於（n+1）^k 的公式
要乘開好像有點花時間。。。
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◆ From: 120.127.36.124
※ 編輯: ms941251 來自: 120.127.36.124 (03/22 21:33)
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03/22 21:35, , 1F
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03/22 21:40, , 2F
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03/22 21:49, , 3F
03/22 21:49, 3F
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03/22 22:57, , 4F
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03/23 01:19, , 5F
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03/24 18:40, , 6F
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03/24 18:41, , 7F
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03/25 12:43, , 8F
03/25 12:43, 8F