Metamath Proof Explorer


Theorem oesuc

Description: Ordinal exponentiation with a successor exponent. Definition 8.30 of TakeutiZaring p. 67. (Contributed by NM, 31-Dec-2004) (Revised by Mario Carneiro, 8-Sep-2013)

Ref Expression
Assertion oesuc ( ( 𝐴 ∈ On ∧ 𝐵 ∈ On ) → ( 𝐴o suc 𝐵 ) = ( ( 𝐴o 𝐵 ) ·o 𝐴 ) )

Proof

Step Hyp Ref Expression
1 limon Lim On
2 rdgsuc ( 𝐵 ∈ On → ( rec ( ( 𝑥 ∈ V ↦ ( 𝑥 ·o 𝐴 ) ) , 1o ) ‘ suc 𝐵 ) = ( ( 𝑥 ∈ V ↦ ( 𝑥 ·o 𝐴 ) ) ‘ ( rec ( ( 𝑥 ∈ V ↦ ( 𝑥 ·o 𝐴 ) ) , 1o ) ‘ 𝐵 ) ) )
3 1 2 oesuclem ( ( 𝐴 ∈ On ∧ 𝐵 ∈ On ) → ( 𝐴o suc 𝐵 ) = ( ( 𝐴o 𝐵 ) ·o 𝐴 ) )