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National and Regional Contests
India Contests
ISI Entrance Examination
2012 ISI Entrance Examination
3
3
Part of
2012 ISI Entrance Examination
Problems
(1)
Array of numbers... isi 2012 #3
Source:
5/13/2012
Consider the numbers arranged in the following way:
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6
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15
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17
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\begin{array}{ccccccc} 1 & 3 & 6 & 10 & 15 & 21 & \cdots \\ 2 & 5 & 9 & 14 & 20 & \cdots & \cdots \\ 4 & 8 & 13 & 19 & \cdots & \cdots & \cdots \\ 7 & 12 & 18 & \cdots & \cdots & \cdots & \cdots \\ 11 & 17 & \cdots & \cdots & \cdots & \cdots & \cdots \\ 16 & \cdots & \cdots & \cdots & \cdots & \cdots & \cdots \\ \vdots & \vdots & \vdots & \vdots & \vdots & \vdots & \ddots \end{array}
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14
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15
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Find the row number and the column number in which the the number
20096
20096
20096
occurs.
ceiling function