Peachy

 

We call a number peachy if every digit in the number is either a  or next to a  For example, the numbers 333, 83, and 303 are all peachy, but the numbers    32523 and 340 are not peachy.   

How many positive 2-digit numbers are peachy?    

 

I think the missing number is a 3.  

 

13,   23,   31,   32,   33,   34,  

35,   36,   37,   38,   39,   43,  

53,   63,   73,   83,   93    

 

Answer:   I found 17 of them.  

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