Posted by Subhotosh Khan on September 18, 2002 at 15:56:52:
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.
: That took 2 steps: the more steps it takes, the MESSIER the formula....
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I think it is called "difference Equations.
here you need to make up a table like this:
2
....10
12.......8
....18......0
30.......8
....26......0
56.......8
....34
90
So the difference is "constantalized" or "Zerofied" - from there there is a standard method (which I forget at this point) to get the equation.