NONLINEAR VARIABILITY OF NGC-4151

We have collected all literature photometric data obtained in the B ba nd for the Seyfert galaxy NGC 4151 over the period 1910-1991, reduced them to the standard B-T photometric system and derived nuclear magnit udes by subtracting the light contribution from the underlying extende d bulge component. The spectral analysis of the light curve shows no e vidence for periodicities. The multifractal analysis clearly indicates a non linear intermittent behaviour, suggesting that the physical mec hanism responsible for the variability of NGC 4151 may be similar to t hose which are at work in the OW 3C 345.