Neka su aa i mm prirodni brojevi, pp neparan prost broj, takav da pma1p^m \mid a - 1 i pm+1a1p^{m+1} \nmid a - 1. Dokažite da

a) pm+napn1p^{m+n} \mid a^{p^n} - 1 za svaki nNn \in \mathbf{N},

b) pm+n+1apn1p^{m+n+1} \nmid a^{p^n} - 1 za svaki nNn \in \mathbf{N}.