题目

The Adventures of Tom SawyerThe Adventures of Tom Sawyer, by Mark Twain, is part of the Barnes & Noble Classics series, which offers quality editions at affordable prices to the student and the general reader. Perhaps the best-loved nineteenth-century American novel, Mark Twain’s tale of boyhood adventure is filled with fun, warmth, and energy. It brings many impressive characters --- the self-confident Tom, his best friend Huck Finn, nice Aunt Polly, and the lovely Beck.The Adventures of PinocchioThe Adventures of Pinocchio is a novel for children by Italian author Carlo Collodi. The fi设数列{an}中的前n项和Sn=14(an+1)2，且an＞0．（1）求a1、a2；（2）求{an}的通项．