You can use GeoGebra to compute the numbers of a sequence, such as figurate numbers. 
     GeoGebra Instruction 1
Algebra     View     under         View     in         Menu.         Sequence(<Expression>, <Variable>, <Start Value>, <End Value>)
where
<Expression>         is               the               expression               defining               an               element               in               the               sequence               (usually               given               as                                or               )               
<Variable>         is               the               variable               used               in               the               expression               (usually               ),               which               is               also               known               as               the               index             of               the               element.               
<Start         Value>         is               the               lowest               value               of               the               index               range               (usually               1)               
<End         Value>         is               the               highest               value               of               the               index               range               (usually               1) 
Example 1
Compute the ten first figurate numbers of
You type
Sequence(n*(n+1), n, 1, 10)
in Algebra View. GeoGebra gives the sequence  
{2, 6, 12, 20, 30, 42, 56, 72, 90, 110}
which contains the figurate numbers you wanted to compute!