Question 295555
3,6,12,24,48...
<pre>
That is a geometric sequence beginning with first term {{{a[1]=3}}},
because to get each succeeding term, we multiply the preceding term 
by 2.

{{{a[n]=a[1]*r^(n-1)}}}

Substitute {{{n=100}}}, {{{a[1]=3}}}, and {{{r=2}}}

{{{a[100]=(3)*(2)^(100-1)}}}

{{{a[100]=3*2^99}}}

Edwin</pre>