Descubra a lógica e complete o próximo elemento

a) (1, 2, 4, 7, 11, 16, ?)
b) (2, 4, 8, 16, 32, ?)
c) (1, 4, 9, 16, 25, 36, ?)
d) (1, 3, 7, 15, 31, ?)
e) (1, 3, 6, 8, 16, ?, ?)
f) (2, 10, 12, 16, 17, 18, 19, ?)
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