Function cofunctionShiftRec

src/compute-engine/rubi/rubi-utils.ts:2535–2550

(
  ce: ComputeEngine,
  e: Expression,
  x: string
)

 * Chapter-4 dispatch rules). */
function hasInertTrig(e: Expression): boolean {
  if (TO_ACTIVE[e.operator] !== undefined) return true;
  return e.ops?.some(hasInertTrig) ?? false;
}

// Inverse functions (CE names: inverse trig `Arcsin…`, inverse hyperbolic
// `Arsinh…`, logarithms) + calculus heads. `InverseFunctionFreeQ[u, x]` is
// True when none of these appear with `x` inside — a guard Rubi uses to keep
// reduction rules from firing on already-integrated-looking subexpressions.
const INVERSE_FNS = new Set([
  'Arcsin',
  'Arccos',
  'Arctan',
  'Arccot',
  'Arcsec',
  'Arccsc',
  'Arsinh',
  'Arcosh',
  'Artanh',
  'Arcoth',