[16] When all the above matters are taken into account we consider that the sentence that was imposed was excessive. The difficulty in framing an appropriate sentence for this man is exacerbated by the limited range of options open under s 92 of the Penalties and Sentences Act as interpreted in R v Hughes[8]. If the benefits of probation are to be obtained, he cannot be concurrently sentenced to more than six months imprisonment. This applicant had already been in custody for 133 days when the sentencing procedure occurred. If a six month sentence could be imposed on top of this, it would mean that a reasonably stiff custodial term would be served followed by the benefits of psychiatric supervision, and such a combined sentence would not in our view be inadequate. However we do not think that it would be open to impose a sentence of imprisonment and probation in such a way as to deprive the applicant of the benefit of the 133 days service of custody by him. If this were done the sentence might be seen as equivalent to about 15 months imprisonment. Section 161 of the Penalties and Sentences Act allows the court to impose a sentence without a specific declaration as to the amount of pre-sentence custody, but when it does so the court fashions a notional term by deducting time served from the sentence that would be otherwise appropriate, commonly treating the time already served as equivalent to twice its nominal value[9]. To do so in this case would in substance be contrary to the requirement in s 92(1)(b) of the Penalties and Sentences Act that "the effect of a probation order is that the offender is sentenced to a term of imprisonment for not longer than six months". It follows that if probation is to be ordered, the maximum imprisonment that could be imposed would be six months, and due credit would have to be given for the time already served. With some hesitation we consider that a sentence of six months imprisonment, with a declaration of 133 days already served, followed by probation would be an inadequate sentence.