How many integers between 17 and 2678 are multiples of 11?

The multiples of 11 between 17 and 2678 form an arithmetic sequence:
22, 33, 44, ……, 2673
The first term, T(1) = a = 22
The common difference, d = 11

T(n) = 2673
a + (n - 1)d = 2673
22 + (n - 1) × 11 = 2673
(n - 1) × 11 = 2651
n - 1 = 241
n = 242

Hence, there are 242 integers.

26788/11 = 243 and change

but the number 11 itself is excluded, so there are just 242

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How many integers between 17 and 2678 are multiples of 11?
22, 33, 44, 55, ....
a_n = 11 (n + 1) 
a_243 = 2674
243 integers are multiples of 11 between 17 and 2678.