Initial data commit

Task/Pythagorean-quadruples/Java/pythagorean-quadruples.java

@@ -0,0 +1,38 @@
+import java.util.ArrayList;
+import java.util.List;
+
+public class PythagoreanQuadruples {
+
+    public static void main(String[] args) {
+        long d = 2200;
+        System.out.printf("Values of d < %d where a, b, and c are non-zero and a^2 + b^2 + c^2 = d^2 has no solutions:%n%s%n", d, getPythagoreanQuadruples(d));
+    }
+
+    //  See:  https://oeis.org/A094958
+    private static List<Long> getPythagoreanQuadruples(long max) {
+        List<Long> list = new ArrayList<>();
+        long n = -1;
+        long m = -1;
+        while ( true ) {
+            long nTest = (long) Math.pow(2, n+1);
+            long mTest = (long) (5L * Math.pow(2, m+1));
+            long test = 0;
+            if ( nTest > mTest ) {
+                test = mTest;
+                m++;
+            }
+            else {
+                test = nTest;
+                n++;
+            }
+            if ( test < max ) {
+                list.add(test);
+            }
+            else {
+                break;
+            }
+        }
+        return list;
+    }
+
+}