| Singular | Plural | |
|---|---|---|
| Nominativ | pentecontarcus | pentecontarci |
| Genitiv | pentecontarci | pentecontarcum, pentecontarcorum |
| Dativ | pentecontarco | pentecontarcis |
| Akkusativ | pentecontarcum, pentecontarcom | pentecontarcos |
| Ablativ | pentecontarco | pentecontarcis |
| Vokativ | pentecontarce | pentecontarci |