🚀 go-pugleaf

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Dear reders ,

 I am looking for real functions A(x) and B(x) which satisfy both  the following constraints :

 (a) < A(x-k), A(x-l) > = delta(k,l). 
     < B(x-k), B(x-l) > = delta(k,l).
     < A(x-k), B(x-l) > = 0. 

 (b) < A"(x-k), B"(x-l) > = 0.

 where the symbol <.,.> stands for the inner product, and delta(.,.) stands
 for the kronecker delta function. k and l are integers. A" and B" are defined
 as the second derivatives of functions A and B.
 
 Any solution or advice will be appreciated. ( Please reply by email : u7811837@cc.nctu.edu.tw )
 
 Thanks in advance.
 
 YMH
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