[Michellefrance6]

Hi.
What's the following numbers in the sequence
1-4-14-51-216-
Many thanks.

Michelle.

[Curlyben]

What do YOU think ?
While we're happy to HELP we wont do all the work for you.
Show us what you have done and where you are having problems..

[Michellefrance6]

Hi,OK - I've tried looking at the differences in the numbers so, between 1 and 4 there is a difference of 3, between 14 and for a difference of 10, 51 and 14 a difference of 37 and between 216 a difference of 165. I've then looked at the 2nd differences and the third differences and finally I end up with 81, so none of the differences are the same!I know that because of the big difference in numbers I will need to multiply. I've tried adding first and then multiplying and it works for the first two:eg. 1 x 3 +1 = 4 4 x 3 + 2 = 1414 x 3 + 3 = 47!! HELP!! Michelle

[ebaines]

Hint: play around with the idea that nth term is (n-1) times the (n-1)th term, plus a factor.

[Michellefrance6]

Hi,This is doing my brain in! I've tried that on the second and third numbers and it works but not on the others.((4-1) x 5) - 1 = 14((14-1) x 4) - 1 = 51 Michelle

[ebaines]

For n-2: 2nd number is equal to the first number times 1, plus ...what?

For n=3: 3rd number is equal to the 2nd times 2, plus what?

For n=4: the 4th number = 3rd number times 3, plus?

etc.

[Michellefrance6]

For n-2: 2nd number is equal to the first number times 1, plus ...what?

For n=3: 3rd number is equal to the 2nd times 2, plus what?

For n=4: the 4th number = 3rd number times 3, plus?

etc.

OK - gottit. Thx.