设级数∑n=1∞=an•n!/nn(a﹥0，a≠e)收敛，则参数a满足____．
a﹤e。解析：因为limn→∞[an+1•(n+1)!/(n+1)n+1]/[(an)•n!)n]=alimn→∞[n/(n+1)]n=a/e所以a/e﹤1时收敛，a/e﹥1时发散，故a﹤e．
设级数∑n=1∞=an•n!/nn(a﹥0，a≠e)收敛，则参数a满足____．
a﹤e。解析：因为limn→∞[an+1•(n+1)!/(n+1)n+1]/[(an)•n!)n]=alimn→∞[n/(n+1)]n=a/e所以a/e﹤1时收敛，a/e﹥1时发散，故a﹤e．
