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 Skip Navigation LinksMath Help > Math Puzzles > 2004 State Logic Quiz > Question 09 > Question 09

Academic Decathlon 2004 State Championship Logic Quiz

Question 09

What are the next two numbers in this sequence?

 2   6  15 28 55 78 119 ____ ____

 

Answer:

152, 207

The nth number in the sequence is n multiplied by the nth prime.

1 x 2 = 2
2 x 3 = 6
3 x 5 = 15
4 x 7 = 28
5 x 11 = 55
6 x 13 = 78
7 x 17 = 119
8 x 19 = 152
9 x 23 = 207

If you have access to the Internet, you can often find the pattern in an integer sequence by looking it up on the OEIS.  This particular sequence is called n*(n-th prime), sequence number A033286.

 

Related pages in this website

See the NEXT puzzle in the Academic Decathlon 2004 Logic Quiz

 

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