Ricoh GXR A16 24-85mm F3.5-5.5 has a 16.0MP APS-C (23.6 x 15.7 mm ) sized CMOS sensor and features Smooth Imaging Engine IV processor. On the other hand, Sony A7c has a 24.0MP Full frame (35.8 x 23.8 mm ) sized BSI-CMOS sensor and features Bionz X processor.
Sony A7c's sensor provides 8MP more than Ricoh GXR A16 24-85mm F3.5-5.5's sensor, which gives a significant advantage in real life. You can print your images larger or crop more freely.
On the other hand, please keep in mind that Max sensor resolution is not the only determinant of resolving power. Factors such as the optical elements, low pass filter, pixel size and sensor technology also affects the final resolution of the captured image.
Below you can see the GXR A16 24-85mm F3.5-5.5 and A7c sensor size comparison.
As seen above, Sony A7c has a 2.3x Larger sensor area than Ricoh GXR A16 24-85mm F3.5-5.5. Larger sensors give photographer more control on the depth of field and blurry background compared to smaller sensor when shot in same focal length and aperture.