Data commit

Task/Jacobsthal-numbers/Rust/jacobsthal-numbers.rust

@@ -0,0 +1,47 @@
+// [dependencies]
+// rug = "0.3"
+
+use rug::integer::IsPrime;
+use rug::Integer;
+
+fn jacobsthal_numbers() -> impl std::iter::Iterator<Item = Integer> {
+    (0..).map(|x| ((Integer::from(1) << x) - if x % 2 == 0 { 1 } else { -1 }) / 3)
+}
+
+fn jacobsthal_lucas_numbers() -> impl std::iter::Iterator<Item = Integer> {
+    (0..).map(|x| (Integer::from(1) << x) + if x % 2 == 0 { 1 } else { -1 })
+}
+
+fn jacobsthal_oblong_numbers() -> impl std::iter::Iterator<Item = Integer> {
+    let mut jn = jacobsthal_numbers();
+    let mut n0 = jn.next().unwrap();
+    std::iter::from_fn(move || {
+        let n1 = jn.next().unwrap();
+        let result = Integer::from(&n0 * &n1);
+        n0 = n1;
+        Some(result)
+    })
+}
+
+fn jacobsthal_primes() -> impl std::iter::Iterator<Item = Integer> {
+    jacobsthal_numbers().filter(|x| x.is_probably_prime(30) != IsPrime::No)
+}
+
+fn main() {
+    println!("First 30 Jacobsthal Numbers:");
+    for (i, n) in jacobsthal_numbers().take(30).enumerate() {
+        print!("{:9}{}", n, if (i + 1) % 5 == 0 { "\n" } else { " " });
+    }
+    println!("\nFirst 30 Jacobsthal-Lucas Numbers:");
+    for (i, n) in jacobsthal_lucas_numbers().take(30).enumerate() {
+        print!("{:9}{}", n, if (i + 1) % 5 == 0 { "\n" } else { " " });
+    }
+    println!("\nFirst 20 Jacobsthal oblong Numbers:");
+    for (i, n) in jacobsthal_oblong_numbers().take(20).enumerate() {
+        print!("{:11}{}", n, if (i + 1) % 5 == 0 { "\n" } else { " " });
+    }
+    println!("\nFirst 20 Jacobsthal primes:");
+    for n in jacobsthal_primes().take(20) {
+        println!("{}", n);
+    }
+}