Question 419143
  <pre><font face = "Tohoma" size = 4 color = "indigo"><b>
Hi
Given the sequence 2,6,12...
{{{f[n] = n(n+1)}}}
{{{f[1] = 1(1+1)= 2}}}
{{{f[2] = 2(2+1)= 6}}}
{{{f[3] = 3(3+1)= 12}}}
etc