求解:有一分数序列:2/1,3/2,5/3,8/5,13/8,21/13...求出这个数列的前20...答:前20项之和:32.660259 附上程序:include <stdio.h> void main(){ int i;float a, b, c, s;a = b = 1.0;c = 0;s = 0;for(i = 0; i < 20; i++){ c = a + b;s = s + c / a;printf("%.0f/%.0f ", c, a);b = a;a = c;} printf("\n%f\n", ...