Posted by T.Gracken on September 18, 2002 at 17:59:36:
In Reply to: guess I'll throw in my 2 cents' worth! posted by Denis Borris on September 18, 2002 at 15:14:08:
: a formula for the sum of any series can be devised, but ONLY IF the difference
: in the terms can be CONSTANTized (copyright 2002, all rights reserved...).
: Take series 1*2, 3*4, 5*6, 7*8, 9*10 ...... (n-1)(n)
: So you have 2, 12, 30, 56, 90 ......
: 1:Differences: 10, 18, 26, 34....
: 2:Differences: 8, 8, 8, ...
: Since we can get a constant difference, we can make up a formula for this one.
I am not convinced...
Given any sequence, you can determine the difference between any two terms and list them.
take the (Fibonacci) sequence 1, 1, 2, 3, 5, 8, 13, 21, ...
We can list the differences: 0, 1, 1, 2, 5, ... {wow, same sequence with a new starting value!).
But, unless by formula you mean just write all terms added, such as 1+1+2+3+5+8+... then I need some more tutoring (which is not unlikely).
...help me understand...