新未名空间

Lefty McGraw, a new promising right-handed pitcher, can throw curve balls or fastballs
(C or F). However, he never throws three curve balls in a row. How many different
sequences of 10 pitches could he throw?

这么简单个题，做得一塌糊涂

相当于：
10位二进制数，不能有连续三个零或更多零，这样的数有几个？

how many 10-bit binary numbers are there if no 3 or more consecutive zeros exist