Hard Math Question! PLEASE PLEASE HELP!

[invitro]

I have a very important math question.... this is going to ba VERY HARD to explain, but bare with me. Ok here it is...

If i give u a sequence of 5 random numbers...
#1 = 5
#2 = 6
#3 = 10
#4 = 2
#5 = 20

And if you found the difference beween the numbers like this
#1 and #2 = D = 1
#3 and D = 9
#4 and D = 7
#5 and D = 13

Now, lets say... i only gave you the last number, total numbers there are in the sequence, and the last difference.. between #4 and #5. It would look like this.

#1 = ?
#2 = ?
#3 = ?
#4 = ?
#5 = 20

Then Differenece between #1 and #2 = x
Then Difference between x and #3 = x
Then Difference between x and #4 = x
Then Difference between x and #5 = 13

Would you be able to work backwards to find the missing numbers?

Is this even possible?

If not, how could you make this work. Maybe instead of finding the difference between the numbers, you could add them or something. But i need a formula, so i can work backwards to find the missing numbers.

PLEASE HELP!
Thank you very much!

If you dont exactly understand what i mean, please specify what further information you require.

For the backwards equation, I believe you can switch the number's around like so:

#5 = 20
X = 13 + #5
X = 13 + 20
X = 33

[Andrew Empson]

Hey Invitro

Are you trying to encrypt and decrypt a numerical sequence? I've looked through your code, and can't see a way to restore your numbers from the last two. Probably the best way to do it would be to convert the sequence to binary, string the digits together, restore it to decimal and supply that number.

I can give you some code to do this if it's any help.

[catocom]

I've got a QBasic program thats designed to do
exactly that and more, called Sequences and Series,
I can email you if you interested.

[invitro]

Yes please email me the program, and no im not making an encryption program.

I just need code to reverse the numbers.
I was thinking, instead of finding the diff. maybe icould add #1 and #2 to make x and then .. no but that wouldent work either.

Hmmm....

??

[email protected]

thanks