rename statics/euler and sync b93 code with main repo

www/statics/euler/Euler_Problem-065_explanation.md

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+Nice algorithm if you see the pattern in the numerators and denominators.
+
+~~~
+denom(n+1) = denom(n) + numer(n) * frac(n)
+numer(n+1) = denom(n)
+~~~
+
+and the fraction at position n is calculated by ([OEIS-A003417](https://oeis.org/A003417)):
+
+~~~
+int GetFrac(int idx)
+{
+	if (idx == 0) return 2;
+	if ((idx-1) % 3 == 0) return 1;
+	if ((idx-1) % 3 == 1) return ((idx+1)/3)*2;
+	if ((idx-1) % 3 == 2) return 1;
+	return 2;
+}
+~~~
+
+The rest is just multiplication and long addition (we exceed the 64bit range) a hundred times ...