Solution

Boo!

By 1847, algebra was so boring, George Boole decided to mix it up!

[[ B or B ]] and 11

[[ D or B ]] and E

19 and F

[[ C and A ]] or 50

21 or 26 or 33

20 or [[ G and E ]] or F

C and B and A

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a is PAIR

b is A000040[1]

c is COLONIES

d is [[ C or 1 ]]

e is GOLDEN RINGS

f is [[ A and A ]]

g is NINE