Question 934112
<pre>
This is Alcuin's sequence.

The formula for the nth term is:

{{{a[n]=system(

matrix(2,4,

Int(n^2/48+1/2), for,even,n,
Int((n+3)^2/48+1/2), for,odd,n))}}}

Where the Int( ) function is the greatest
integer function.

2013 is odd, so

{{{Int((2013+3)^2/48+1/2)=84672}}}

Edwin</pre>