I'll just make a manual computation on how 1 member recruits his members until week 5. Then multiply the sum by 2.
old new
1: 1
2: 1 x 3 = 3 ⇒ 1 3 *only new members recruit 3 more
3: 3 x 3 = 9 ⇒ 4 9
4: 9 x 3 = 27⇒ 13 27
5: 27 x 3 = 81 ⇒ 40 81
40 + 81 = 121. Total number of members under 1 founding member.
121 x 2 founding members = 242 total number of members within 5 weeks.

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Divide by factor of 4.
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<em>*Or divide by the factor of 2 twice</em>


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Divide by factor of 13.
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Combine into single fraction.
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Answer: The factors are 2, 4 and 13--------------------------------------------------------------------------
Answer:
It should be 14400 square inches. Sorry if i'm wrong