数列\(\{a_n\}\)共11项,\(a_1=0,a_{11}=4\),且\(|a_{k+1}-a_{k}|=2,k=1,2,\cdots,10\) 求满足条件的不同的数列的个数______ 解答:\(a_{k+1}-a_{k}\)为2或者-2.设有 \(x\)个2,和\(10-x\)个-2.故\(2x-2(10-x)=4\),得\(x=6\)故有\(C_{10}^6\)不同的数列. 练习: 数列\(\{a_n\}\)共21项,满足\(|a_{k+1}-a_{k}|=1,(k=1,2,\cdo…