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21 (?????)

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10	11	12	13	14	15	16	17	18	19
20	21	22	23	24	25	26	27	28	29
30	31	32	33	34	35	36	37	38	39
40	41	42	43	44	45	46	47	48	49
50	60	70	80	90	100	200	300	400	500
1,000 2,000 10,000 100,000 600,000 1,000,000
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