How can I create a vector using a step index, for example, using the function output f:=1/i+1 and alternate it with a zero

 that produces a vector such as,  0,1/2,0,1/3,0,1/4,0,1/5.....?

Every attempt I tried failed.

Hi,

I am presented with a list of known roots to a polynomial. How can I reconstruct the original polynomial with a variable "x"  from the given roots?

The list of roots is: [-1/2,2/3,7/3,4+3I,4-3I]

I am trying to get the output listed into a vector or list, but I am unsuccessful. I get the error code "improper sequence". but the expression works:

N:=24

while N>1 do if evalb(type(N,even)=true) then N:=N/2;print(N);else N:=3*N+1;print(N);end if;end do;

The output generated is:

12

6

10

5

16

8

4

2

1

I would like to have the output as a list or a vector with two numbers,...