Alternating Triangles Given a strictly positive integer n (therefore 0 isn't a valid test case), produce an approximate triangle of height n.

A non-programmatic process of drawing the picture

Initially we start with the base of the triangle.

|


So, we want to draw a triangle of a height of 5. First we know that all the |'s align on a straight line, and there is a missing | on every even position.

|

|

|


Then, we insert the /'s onto these empty lines, where every / has 1 more preceding space than the next /. The lowest / starts at 1 space.

|
  /
|
 /
|


More reference outputs + Sample program

Here's what the program should output for inputs 1 to 9. A sample program is available if you still don't understand the specification.

For those that don't see that it's a triangle: Take a look at this. Scroll the picture really quickly. You will see the two sides of a triangle.

==== 1: ====
|
==== 2: ====
 /
|
==== 3: ====
|
 /
|
==== 4: ====
  /
|
 /
|
==== 5: ====
|
  /
|
 /
|
==== 6: ====
   /
|
  /
|
 /
|
==== 7: ====
|
   /
|
  /
|
 /
|
==== 8: ====
    /
|
   /
|
  /
|
 /
|
==== 9: ====
|
    /
|
   /
|
  /
|
 /
|


Specification


Leading/Trailing whitespace is allowed.
The string has to be joined with newlines, outputting a string list is not allowed.
Husk, 12 bytes

↔↑ṁe"|"¡Θ" /


Try it online!

Builds the infinite triangle upside-down, then takes the required number of lines and reverses them before printing.

Explanation

↔↑ṁe"|"¡Θ" /
       ¡        Repeat and accumulate results:
        Θ          prepend a space
         " /       starting from the string " /"
                   (this will create all the lines of the slanted side)
  ṁ             For each line:
   e"|"            put it in a list with a "|" line
  ṁ             and merge all these lists together
 ↑              Take the number of lines required by the input
↔               Reverse the result