| [ QuizWit ] in KIDS 글 쓴 이(By): iLUSiON (띠띠빤쮸) 날 짜 (Date): 2004년 5월 25일 화요일 오전 08시 47분 57초 제 목(Title): Re: 2XP QUIZ V. hehe... easy... let tail be 1 and head be 0. there are 6 1's and 14 0's. 0000000000000 <--- hope there are 14 0's... ^^ now you put sticks (1's) somewhere between 0's such that there are no more than 5 0's between sticks. oho... this seems harder than i thought. hehe.. hi jhshin.... nice problem.... :) why don't i try iterative method.... let X(n) be the number of events that gurantee the above condition when n coins are thrown. obviously X(6)=1, X(7)=7... X(8)= ... now you set up difference equation and solve for X(20). hehe cool enough? iLUSiON - le plus grand de tous http://cyworld.nate.com/ilusion |