Counting the solutions
LzyRapx C_K_Yang liuguangxi rhguad1 Min_25 C3PO Philippe_57721 gerrob sinan hervas benito255 Buri nielkh
Public  10/17/15  7xp  Math  5.3% 
How many pairs of positive integers $(a,b) \le 10^9 $ are there such as :
$$ \frac{a^2}{2ab^2  b^3 + 1} \textrm{ is an integer} $$
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