6
Jelly, 4 3 bytes
ÆḞ⁺
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ÆḞ⁺
⁺ # Twice:
ÆḞ # Nth fibonacci
-1 byte thanks to Unrelated String
05AB1E, 4 bytes
ÅfÅf
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ÅfÅf
Åf # Nth fibonacci
Åf # Nth fibonacci
flax, 4 bytes
;f;f
;f;f
;f # Nth fibonacci
;f # Nth fibonacci
Actually, 2 bytes
FF
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