Cases 5 and 7 are identical, and I believe they are both wrong. 5 x 142857 = 714285. Isn't this a parasitic number? What am I missing?
There is 4, not 5
I mistyped. 4 x 142857 = 571428, which is a shift right of 2. Incidentally, both n = 4 and 5 both make parasitic pairs with 142857.
Thus it is not a 4parasitic number. It doesn't meet the definition. Nevertheless is a great example of a cyclic number. You can get different cyclic permutations when multiply 142857 by 1, 2, 3, 4, 5 and 6. For 5 you got shift by one digit, therefore it's 5parasitic.
Ahhh, I see! Thanks, Jan  I get it now!
Test  Status  Code Input and Output 

1  Pass 
x = 128205;
n = 4
y_correct = true;
assert(isequal(parasitic(x,n),y_correct))
n =
4

2  Pass 
x = 179487;
n = 4;
y_correct = true;
assert(isequal(parasitic(x,n),y_correct))

3  Pass 
x = 179487;
n = 3;
y_correct = false;
assert(isequal(parasitic(x,n),y_correct))

4  Pass 
x = 142857;
n = 5;
y_correct = true;
assert(isequal(parasitic(x,n),y_correct))

5  Fail 
x = 142857;
n = 4;
y_correct = false;
assert(isequal(parasitic(x,n),y_correct))

6  Pass 
x = 142657;
n = 5;
y_correct = false;
assert(isequal(parasitic(x,n),y_correct))

7  Fail 
x = 142857;
n = 4;
y_correct = false;
assert(isequal(parasitic(x,n),y_correct))

8  Pass 
x = 1012658227848;
n = 8;
y_correct = true;
assert(isequal(parasitic(x,n),y_correct))

9  Pass 
x = 1012658227848;
n = 4;
y_correct = false;
assert(isequal(parasitic(x,n),y_correct))

10  Pass 
x = 142857;
n = 7;
y_correct = false;
assert(isequal(parasitic(x,n),y_correct))

11  Pass 
x = 12;
n = 2;
y_correct = false;
assert(isequal(parasitic(x,n),y_correct))

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