After the true fraction A7 is changed into a decimal, if the sum of several consecutive digits from the first digit after the decimal point is 1992=______ ．

17=0.142857… (6-digit decimal cycle), 27 = 0.285714 (6-digit decimal cycle), 37 = 0.428571 (6-digit decimal cycle), 47 = 0.571428 (6-digit decimal cycle), 57 = 0.714285 (6-digit decimal cycle), 67 = 0.857142 (6-digit decimal cycle), no matter how many parts of seven, the cycle section is those numbers (142857), the sum of a cycle section is: 1 + 4 + 2 + 8 + 5 + 7 = 271992 △ 27 = 73 21, 21 is less than 27 by 6, only 4 + 2 = 6 in the continuous number, so the cyclic section of this fraction should be: 857142, so a = 6

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