Bounded Dirichlet inverse

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Every completely-multiplicative sequence has Dirichlet inverse bounded by [math]\displaystyle{ 1 }[/math], and the longest discrepancy-2 sequence with this property has length [math]\displaystyle{ 246 }[/math]. (Are all such maximal sequences completely-multiplicative?)

The longest discrepancy-2 sequence with Dirichlet inverse bounded by [math]\displaystyle{ 2 }[/math] has length [math]\displaystyle{ 389 }[/math]. Here is an example:

+1, -1, +1, +1, -1, -1, +1, -1, -1, +1, -1, +1, +1, -1, -1, +1,
-1, +1, +1, -1, +1, +1, -1, -1, +1, -1, -1, +1, -1, +1, +1, -1,
-1, +1, -1, -1, +1, -1, +1, +1, -1, -1, +1, -1, +1, +1, -1, +1,
+1, -1, -1, +1, -1, +1, +1, -1, +1, +1, -1, -1, +1, -1, -1, +1,
-1, +1, +1, -1, -1, +1, -1, +1, +1, -1, +1, +1, -1, -1, -1, -1,
+1, +1, -1, +1, +1, -1, -1, +1, +1, -1, +1, -1, +1, +1, -1, -1,
+1, -1, +1, +1, -1, +1, -1, -1, -1, +1, -1, -1, +1, -1, +1, +1,
+1, -1, +1, -1, -1, +1, -1, +1, +1, -1, -1, +1, -1, +1, -1, -1,
+1, +1, +1, -1, +1, -1, +1, +1, -1, +1, -1, -1, -1, +1, -1, -1,
+1, -1, +1, +1, +1, -1, -1, -1, +1, +1, -1, +1, +1, +1, -1, +1,
-1, -1, +1, -1, +1, +1, -1, -1, +1, -1, -1, +1, -1, +1, +1, -1,
-1, -1, +1, +1, +1, -1, +1, +1, -1, -1, +1, -1, -1, +1, -1, +1,
+1, -1, -1, +1, +1, -1, -1, -1, +1, +1, -1, -1, +1, +1, +1, +1,
-1, +1, -1, -1, -1, +1, -1, +1, +1, -1, +1, +1, -1, -1, +1, -1,
-1, -1, +1, +1, +1, -1, -1, +1, -1, +1, +1, -1, -1, +1, +1, -1,
-1, -1, +1, +1, -1, +1, +1, -1, -1, +1, -1, -1, +1, +1, +1, +1,
-1, -1, +1, -1, +1, -1, -1, +1, +1, -1, +1, +1, -1, -1, +1, -1,
+1, +1, -1, -1, +1, +1, -1, +1, -1, +1, -1, -1, -1, +1, -1, +1,
+1, -1, +1, +1, -1, -1, +1, -1, +1, -1, -1, +1, +1, +1, -1, +1,
-1, -1, +1, -1, -1, +1, +1, -1, +1, -1, +1, -1, -1, +1, +1, -1,
-1, +1, -1, +1, +1, -1, +1, +1, -1, -1, +1, -1, -1, +1, -1, +1,
-1, +1, +1, +1, -1, -1, +1, -1, +1, +1, -1, -1, +1, -1, -1, +1,
-1, +1, +1, +1, -1, -1, +1, -1, +1, -1, +1, +1, -1, +1, -1, -1,
+1, +1, -1, -1, +1, -1, +1, +1, -1, +1, -1, -1, -1, +1, +1, -1,
+1, -1, -1, +1, +1

The longest discrepancy-2 sequence with Dirichlet inverse bounded by [math]\displaystyle{ 3 }[/math] has length at least [math]\displaystyle{ 489 }[/math].