Formal target: Corpus.OEIS67857.conjecture
The terms are not all positive.
Exact formal statement
∀ (n : Nat),
LT.lt.{0} 0 n →
Iff (LT.lt.{0} (Corpus.OEIS67857.a n) 0)
(And (Odd.{0} (DFunLike.coe.{1, 1, 1} ArithmeticFunction.cardDistinctFactors n))
(LE.le.{0} 3 (DFunLike.coe.{1, 1, 1} ArithmeticFunction.cardDistinctFactors n)))This target is a formal statement, not a proof of the problem.
Environment availability: available.