SOLUTION: What kind of sequence is this? 191, 175, 159, 143 arithmetic, geometric, both, neither

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Question 1086901: What kind of sequence is this?
191, 175, 159, 143
arithmetic, geometric, both, neither

Answer by MathLover1(20850) About Me  (Show Source):
You can put this solution on YOUR website!

191, 175, 159, 143 ,...
see if there is constant difference between terms
175-191=-16
143-159=-16
so, d=-16
check:
a%5B1%5D=191,
a%5B2%5D=191-16=175,
a%5B3%5D=175-16=159,
a%5B4%5D=159-16=143+,...

find a%5B0%5D=>
+a%5B0%5D-16=191
a%5B0%5D=191%2B16
a%5B0%5D=207
so, in general n-th term formula is:
a%5Bn%5D+=+207+-+16n where n=1,2,3,....
since by definition, an arithmetic sequence goes from one term to the next by always adding (or subtracting) the same value known as "common difference", in your case we have an arithmetic+sequence