A Nice Equation With Positive Integers

[@nevgongivuup]

very elegant

[@시리우스포카칩]

2nd method is very smart

[@DJ.Nihad6174]

Continued finite fraction. 2nd method is easier than first

[@yurenchu]

[a, b, c, d] = 13/5 = *2* + 3/5 ==> a = *2*
[b, c, d] = 1/(3/5) = 5/3 = *1* + 2/3 ==> b = *1*
[c, d] = 1/(2/3) = 3/2 = *1* + 1/2 ==> c = *1*
[d] = 1/(1/2) = 2/1 = *2* ==> d = *2*
==>
(a, b, c, d) = (2, 1, 1, 2)