length	A	U	C	G
16	0	0	0	0
17	1	0	0	0
18	0	0	0	0
19	2	0	0	0
20	16	1	3	4
21	8	1	3	1
22	7	1	1	1
23	13	2	3	0
24	5	1	3	1
25	5	2	1	1
26	1	1	1	0
27	2	0	0	0
28	3	2	1	1
29	1	0	0	0
30	5	1	0	0
31	0	0	2	0
32	0	0	0	0
33	0	0	0	0
34	0	0	0	0
35	0	0	0	0
36	0	0	0	0
37	0	0	0	0
38	0	0	0	0
39	0	0	0	0
40	0	0	0	0
41	0	0	0	0
42	0	0	0	0
43	0	0	0	0
44	0	0	0	0
45	0	0	0	0
46	0	0	0	0
47	0	0	0	0
48	1	0	0	0
49	0	0	0	0
50	0	0	0	0