nostr:npub1pt6l3a97fvywrxdlr7j0q8j2klwntng35c40cuhj2xmsxmz696uqfr6mf6 nostr:npub1srhg4hk63ew68kepu0znazgf9tdl089dkur5artp440htxqrc8zsqz8g90 i thought empty sets cant have inf or sups by definition.