Reset residue toggle after default-limit residue test

PerfectNumbers.Core.Tests/MersenneNumberResidueGpuTesterTests.cs

@@ -21,9 +21,57 @@ public class MersenneNumberResidueGpuTesterTests
         RunCase(tester, 29UL, 37UL, expectedPrime: false);
         RunCase(tester, 31UL, 1_000UL, expectedPrime: true);
         RunCase(tester, 89UL, 1_001UL, expectedPrime: true);
+        RunCase(tester, 107UL, 1_001UL, expectedPrime: true);
         RunCase(tester, 127UL, 1_001UL, expectedPrime: true);
     }
 
+    [Theory]
+    [InlineData(false)]
+    [InlineData(true)]
+    [Trait("Category", "Fast")]
+    public void Scan_handles_multiple_sets_without_false_positives(bool useGpuOrder)
+    {
+        var tester = new MersenneNumberResidueGpuTester(useGpuOrder);
+
+        bool isPrime = true;
+        bool exhausted = false;
+        UInt128 perSetLimit = 1_666_667UL;
+        UInt128 setCount = 3UL;
+        UInt128 overallLimit = 5_000_000UL;
+
+        tester.Scan(
+            127UL,
+            (UInt128)127UL << 1,
+            LastDigitIsSeven(127UL),
+            perSetLimit,
+            setCount,
+            overallLimit,
+            ref isPrime,
+            ref exhausted);
+
+        isPrime.Should().BeTrue();
+        exhausted.Should().BeTrue();
+
+        isPrime = true;
+        exhausted = false;
+        perSetLimit = 20_000_000UL;
+        setCount = 5UL;
+        overallLimit = 100_000_000UL;
+
+        tester.Scan(
+            107UL,
+            (UInt128)107UL << 1,
+            LastDigitIsSeven(107UL),
+            perSetLimit,
+            setCount,
+            overallLimit,
+            ref isPrime,
+            ref exhausted);
+
+        isPrime.Should().BeTrue();
+        exhausted.Should().BeTrue();
+    }
+
     private static void RunCase(MersenneNumberResidueGpuTester tester, ulong exponent, ulong maxK, bool expectedPrime)
     {
         bool isPrime = true;