-------- Original Message -------- Subject: On Automatic solution of recurrence relations Date: Sat, 29 Mar 2008 12:12:29 -0500 From: Alexander Povolotsky apovolot@gmail.com To: alessandro.zaccagnini@unipr.it, bagnara@cs.unipr.it

Dear Roberto and Alessandro,

PURRS is great ! - Many thanks for making it available online !

But could you may be consider complementing PURRS with the tool, which would try to figure out whether (or not) given integer sequence <with first "few" (unknown exact number) terms constitute "initial conditions"> is recurrence based ?

For example consider Engel expansion of Pi:

1, 1, 1, 8, 8, 17, 19, 300, 1991, 2492, 7236, 10586, 34588, 63403, 70637, 1236467 , 5417668, 5515697, 5633167, 7458122, 9637848, 9805775, 41840855, 58408380, 213130873

Could above sequence be by any chance recurrence based ?

Best Regards, Alexander R. Povolotsky