Answer:
Explanation:
a₁ = 1
a₂ = 8 = 1 + 7 = a₁ + 7
a₃ = 15 = 1 + 7 + 7 = a₁ + 7×2
a₄ = 22 = 1 + 7 + 7 + 7 = a₁ + 7×3
Therefore:
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