We prove two conjectures from the Ramanujan Machine project (Nature 2021): the continued fraction PCF((2n+1)(5n²+5n+2), −16n⁶) = 12/(7ζ(3)) via the Domb Apéry limit on level 6, and PCF((2n+1)(3n²+3n+1), −n⁶) = 8/(7ζ(3)) via the A290575 Apéry limit on level 8. Both proofs use the same method: eta-product parametrization, Eichler integrals, and Atkin–Lehner extraction of the ζ(3) period.
Alex Shvets (Fri,) studied this question.