Proof step

Ore-algebra identity of two definitions

All-n equality of two definitions

Concludes

shift_x_plus_one of basis_map_A013609 of Triangle of Narayana numbers T(n,k) = C(n-1,k-1)*C(n,k-1)/k with 1 <= k <= n, read by rows. Also called the Catalan tr…

Premises

none: a direct theorem check

Theorem

polytool ?

Checked

polytool replayed · Lean not attempted