Arith.sc_idx: def of bend-collections-laws-math@1.0.0.0
Import: import bend-collections-laws-math@1.0.0.0/proofs/lib/arith.bend as Arith
Lines 143-149 of bend-collections-laws-math@1.0.0.0/proofs/lib/arith.bend: https://jend.leeeet.dev/read.txt?path=bend-collections-laws-math@1.0.0.0/proofs/lib/arith.bend&start_line=143&end_line=149

import Base

# 2^(k + j) x == 2^k (2^j x)
def sc_idx(+k: Nat, +j: Nat, +x: Nat) -> {sc(Nat.add(k, j), x) == sc(k, sc(j, x)) : Nat}:
  match k:
    case 0n:
      {==}
    case 1n+p:
      Equal.cong(Nat, Nat, Nat.double, sc(Nat.add(p, j), x), sc(p, sc(j, x)), sc_idx(p, j, x))

Uses (5):
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=Equal.cong
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=Nat
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=Nat.add
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=Nat.double
  https://jend.leeeet.dev/definition.txt?path=bend-collections-laws-math@1.0.0.0/proofs/lib/arith.bend&name=sc