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Mon 13 Jun, 2005 09:59 am
anyway to solve this type of question?
ummm, depending on the nature of the sequence, for arithmetic sequences:
Tn = a + d(n-1) where [a] is the initial term, [d] is the increment and [n] is the number of terms
for geometric sequences:
Tn = ar^(n-1) --> [a] times [r to the power of n -1]
hope this helps.
Sneaky Sequences
Prime 1,2,3,5,7,11,13,17,19,23,29,31,....
Alphabetic 5,4,8,1,9,7,6,3,2,0
Fibonacci 1,1,2,3,5,8,13,21,34,55,....,F(n)+F(n-1)
Triangular 1,3,6,10,15,21,....n(n+1)/2
(and pentagonal, sexagonal, heptagonal, octagonal well you see the possibilities (note square numbers are square sequences.)
Rap
can you help me find the nth term of this sequence?
0,11,44,110,220
385
The nth term is (11/6)*(n^3 - n)
Take the difference of the terms. Then take the difference of the differences, and so on. If it is a polynomial function, then you will end up with all zeros. The order of the polynomial function is one less than the number of times you took the differences
0 11 44 110 220
11 33 66 110
22 33 44
11 11
0
Of course, you can't be certain this is the solution. There are an infinite number of sequences that start with 0, 11, 44, 110, 220.