def rhd.c2a
import bend-kit-collections@0.1.4.1/nat_order.bend as NatOrderimport Base
636def rhd.c2a(+l: Nat, +x: Nat, +y: Nat, +b: Nat, h3: LE(1n+Nat.mul(3n, l), Nat.add(b, Nat.add(y, x))), hd: LE(Nat.mul(2n, b), Nat.add(y, x)), h6: LE(y, Nat.mul(3n, x))) -> LE(l, Nat.mul(3n, x)):
637 by_contra(l, Nat.mul(3n, x), ng => rhd.c2a.k(l, x, y, b, ng, h3, hd, h6))