Given a website with multiple webpages and numerous users accessing it, where each user has a specific access pattern (e.g., user 1: x->y->z->a->b->c->d->e->f, user 2: z->a->b->c->d, etc.), determine the top 3 most frequently occurring k-page sequences. For example, with k=3, the result for the provided access patterns would be: a->b->c, b->c->d, z->a->b.