In that case, I think cyclopentanone could be the product.
This would be my thinking. Because ozone is the second step, then elimination must be occurring (if NaNH2/NH3 were the reagent, this would seem more plausible, none the less). Ozone formally gives a dialdehyde plus H2O2. H2O2 plus an aldehyde gives an aldehyde acid (plus some diacid). If BaO were not present, then the diacid seems plausible, but it would form a salt with barium. No aldol products are listed so it cannot be an aldol product of the dialdehyde. An intramolecular Claisen of the enolate of the aldehyde could give 2-oxocyclopentanecarboxaldehyde. A retro-Claisen by attack upon the aldehyde could liberate Formica acid and give the enolate of cyclopentanone. Tautomerization and neutralization would give te ketone. Just guessing.