Calculate 1 × 4 + 4 × 7 + 7 × 10 +... + 19 × 22 + 22 × 25
=4*8+10*20+16*32+22*44=1712
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- 1. 1 * 1 / 4 + 4 * 1 / 7 + 7 * 1 / 10 + 10 * 1 / 13 + 13 * 1 / 16 + 16 * 1 / 19 + 19 * 1 / 22?
- 2. Calculation: 1 / 1 × 4 + 1 / 4 × 7 + 1 / 7 × 10 + 1 / 10 × 13 + 1 / 13 × 16 + 1 / 16 × 19 + 1 / 19 × 22 =?
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- 11. The number of a column is grouped as follows: (1), (4,7), (10,13,16), (19,22,25,28) What's the row and position of 2005?
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