Question 982792
<pre>
First I found the differences

2,12,36,80

I subtracted the squares 1,4,9,16 from those differences

1,8,27,64

I recognized those as the cubes.

So to get the next term, we add the square and the cube of the
number of the term

The recursion formula is

a<sub>n+1</sub> = a<sub>n</sub> + n<sup>2</sup> + n<sup>3</sup>, a<sub>1</sub> = 1 
 
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Start with 1
Add 1<sup>2</sup>+1<sup>3</sup>, which is 1+1=2, get 3
Add 2<sup>2</sup>+2<sup>3</sup>, which is 4+8=12, get 15
Add 3<sup>2</sup>+3<sup>3</sup>, which is 9+27=36, get 51
Add 4<sup>2</sup>+4<sup>3</sup>, which is 16+64=80, get 131
Add 5<sup>2</sup>+5<sup>3</sup>, which is 25+125=150, get 281

Edwin</pre>