A = {1, 2, 3, 5, 6, 10, 15, 30}
B = {1, 2, 3, 4, 5, 6, 8, 10, 12, 15, 20, 24, 30, 40, 60, 120}
C = {1, 3, 5, 15}
D = {1, 3}
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{1, 2, 3, 5, 6, 10, 15, 30} ∩ {1, 2, 3, 4, 5, 6, 8, 10, 12, 15, 20, 24, 30, 40, 60, 120} ∩ {1, 3, 5, 15} ∩ {1, 3} = {1, 3}
{1, 2, 3, 5, 6, 10, 15, 30} ∪ {1, 2, 3, 4, 5, 6, 8, 10, 12, 15, 20, 24, 30, 40, 60, 120} ∪ {1, 3, 5, 15} ∪ {1, 3} = {1, 2, 3, 4, 5, 6, 8, 10, 12, 15, 20, 24, 30, 40, 60, 120}
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{1, 2, 3, 5, 6, 10, 15, 30} ∪ {1, 2, 3, 4, 5, 6, 8, 10, 12, 15, 20, 24, 30, 40, 60, 120} = {1, 2, 3, 4, 5, 6, 8, 10, 12, 15, 20, 24, 30, 40, 60, 120}
{1, 2, 3, 4, 5, 6, 8, 10, 12, 15, 20, 24, 30, 40, 60, 120} ∩ {1, 3, 5, 15}= {1, 3, 5, 15}
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{1, 2, 3, 4, 5, 6, 8, 10, 12, 15, 20, 24, 30, 40, 60, 120} ∩ {1, 3, 5, 15} = {1, 3, 5, 15}
{1, 2, 3, 5, 6, 10, 15, 30} ∪ {1, 3, 5, 15} = {1, 2, 3, 5, 6, 10, 15, 30}
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{1, 2, 3, 5, 6, 10, 15, 30} \ {1, 3, 5, 15} = {2, 6, 10, 30}
{2, 6, 10, 30} ∩ {1, 3} = {}
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{1, 2, 3, 4, 5, 6, 8, 10, 12, 15, 20, 24, 30, 40, 60, 120} \ {1, 2, 3, 5, 6, 10, 15, 30} = {4, 8, 12, 20, 24, 40, 60, 120}
{4, 8, 12, 20, 24, 40, 60, 120} ∩ {1, 3} = {}