Question 176909
1) Looks like you subtract 2 from the previous term to get the next term.
Or start at 3 and subtract 2 at each successive term.
{{{a[1]=3-2(1-1)=3}}}
{{{a[2]=3-2(2-1)=3-2=1}}}
{{{a[3]=3-2(3-1)=3-4=-1}}}
{{{a[4]=3-2(4-1)=3-6=-3}}}
{{{a[5]=3-2(5-1)=3-8=-5}}}
-5 would be the next term.
{{{a[n]=3-2(n-1)=3-2n+2=5-2n}}}
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2) Looks like each term is a product of the cubes with (-3) 
{{{a[1]=(-3)*(1)^3=-3}}}
{{{a[2]=(-3)*(2)^3=-24}}}
{{{a[3]=(-3)*(3)^3=-81}}}
{{{a[4]=(-3)*(4)^3=-192}}}
{{{a[5]=(-3)*(5)^3=-375}}}
{{{a[n]=(-3)*n^3}}}
-375 would be the next term.
{{{a[n]=(-3)*n^3}}}