To identify the wrong number in the series 2, 3, 13, 37, 86, 167, 288, we need to observe the pattern in the sequence. Let's analyze the progression between each number to establish a rule:
We hypothesize that these numbers could follow a specific increment pattern, for which we calculate the differences between consecutive terms:
3 - 2 = 1
13 - 3 = 10
37 - 13 = 24
86 - 37 = 49
167 - 86 = 81
288 - 167 = 121
Observing these differences: 1, 10, 24, 49, 81, 121, we see they do not follow a simple arithmetic or geometric progression. However, further inspection shows a potential link to perfect squares:
1 = 12 |
10 does not match any perfect square increment pattern |
24 does not match any perfect square increment pattern |
49 = 72 |
81 = 92 |
121 = 112 |
To align this sequence towards perfect squares, the differences 10 and 24 must be corrected. Observe:
Assume the second difference should also reflect perfect square pattern:
1, 4, 9, 16, 25, etc., leads us to expect 4 after 1, replacing 10.
This correction fits a perfect square model where:
New sequence: 2, 3, (3+4)=7, 7+9=16, 16+16=32, 32+25=57, (following this adjusted logic)
The incorrect number is hence:
13
Let \( T_r \) be the \( r^{\text{th}} \) term of an A.P. If for some \( m \), \( T_m = \dfrac{1}{25} \), \( T_{25} = \dfrac{1}{20} \), and \( \displaystyle\sum_{r=1}^{25} T_r = 13 \), then \( 5m \displaystyle\sum_{r=m}^{2m} T_r \) is equal to:
Find the missing code:
L1#1O2~2, J2#2Q3~3, _______, F4#4U5~5, D5#5W6~6