The title of this Deke Leonard composition is also rendered "7171 551". The working title was actually the phone number of Mike Nesmith, who had been a member of The Monkees. Being an American, he had a 10-digit phone number, but according to Roger Trenwith in The Progressive Aspect, Deke decided he couldn't use that for the actual track, so the title was changed, although the record label printed the first batch of the LP with the original.
The original recording was for the 1974 Iceberg album wherein it runs to around 5 minutes 15 seconds. It has also been recorded by Man, of which Deke was a founder member. "7171-551" is the opening track of the live double Maximum Darkness which was recorded at The Roundhouse in North London, May 1975. Here it runs to slightly over eleven minutes.
Suggestion credit: Alexander Baron - London, England, for above 2