Preface

 The quiz I found on the internet was interesting, so I thought it a little.


A quiz is a following.

Is the next one?
1 +  4 =  5
2 +  5 = 12
3 +  6 = 21
8 + 11 = ?


In my opinion it will be as follows.

1: 1 +  4 =  5
2: 2 +  5 = 12
3: 3 +  6 = 21
4: 8 + 11 = 52
 invisible number
I think that the 4th standard pattern is a 4+7=32.
I assumed, an order of 1,2,3 and 4,5,6 are the trick for mislead.


1: 1 +  4 x1 =  5
2: 2 +  5 x2 = 12
3: 3 +  6 x3 = 21
4-7 : If it is acceptable this part.
8: 8 + 11 x8 = 96

1 +  4 =  5  operator override
 +: = (equal)
 a=b: b%a (modulo)
2 +  5 = 12
3 +  6 = 21
8 + 11 = n n:19,30,41, 52, 63,74,..
a b d  a = d % b


Conclusion

 It's a very simple thing. It is you yourself that complicates the problem.