Smita04 wrote:
For positive integer m, the m-th heptagonal number is given by the formula (5m^2 – 3m)/2. For positive integer n, the n-th triangular number is the sum of the first n positive integers. Which of the following is true for k, the smallest triangular number that is also heptagonal?
m
(A) 33 ≤ k ≤ 40
(B) 41 ≤ k ≤ 48
(C) 49 ≤ k ≤ 56
(D) 57 ≤ k ≤ 64
(E) 65 ≤ k ≤ 72
Bunuel, can you please help with this one?
hey thanks for the beautiful question
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