Je pense que j'ai vu leur numéro de téléphone quelque part

Question

"I think that I saw their phone number" : As "I" is the subject for both verbs i.e. "think" and "saw", would "Je pense avoir vu leur numéro quelque part" be an acceptable alternative here, or would that just be wrong?

Accepted Answer

Bonjour Paul,
You are right, Paul! Both are correct: penser que / penser + [past infinitive]. It has now been amended. 
I hope this is helpful.
Bonne journée !

Answer

Bonjour Paul,
'Penser + [infinitive]' is used to express 'to plan to do [sth]' or 'to hope to' while 'penser que' will be translated as 'to think (that)'.
So in this instance, you wouldn't have 'penser + [infinitive]'. 
I hope this is helpful.
Bonne journée !

Answer

But is that true for penser + [past infinitive]?Google phrase search gives a lot of hits for "pense avoir vu" or "pensait avoir vu".