Add all threes sequence (TheAlgorithms#352)

Author: VincentDawn

Algorithms.Tests/Sequences/AllThreesSequenceTests.cs

@@ -0,0 +1,18 @@
+using Algorithms.Sequences;
+using FluentAssertions;
+using NUnit.Framework;
+using System;
+using System.Linq;
+using System.Numerics;
+
+namespace Algorithms.Tests.Sequences;
+public class AllThreesSequenceTests
+{
+    [Test]
+    public void First10ElementsCorrect()
+    {
+        var sequence = new AllThreesSequence().Sequence.Take(10);
+        sequence.SequenceEqual(new BigInteger[] { 3, 3, 3, 3, 3, 3, 3, 3, 3, 3 })
+            .Should().BeTrue();
+    }
+}

Algorithms/Sequences/AllThreesSequence.cs

@@ -0,0 +1,26 @@
+using System.Collections.Generic;
+using System.Numerics;
+
+namespace Algorithms.Sequences;
+
+/// <summary>
+///     <para>
+///         The all threes sequence.
+///     </para>
+///     <para>
+///         OEIS: https://oeis.org/A010701.
+///     </para>
+/// </summary>
+public class AllThreesSequence : ISequence
+{
+    public IEnumerable<BigInteger> Sequence
+    {
+        get
+        {
+            while (true)
+            {
+                yield return 3;
+            }
+        }
+    }
+}

README.md

@@ -152,6 +152,7 @@ find more than one implementation for the same objective but using different alg
     * [A007318 Binomial](./Algorithms/Sequences/BinomialSequence.cs)
     * [A007395 All Twos](./Algorithms/Sequences/AllTwosSequence.cs)
     * [A010051 Binary Prime Constant](./Algorithms/Sequences/BinaryPrimeConstantSequence.cs)
+    * [A010701 All Threes](./Algorithms/Sequences/BinaryPrimeConstantSequence.cs)
     * [A011557 Powers of 10](./Algorithms/Sequences/PowersOf10Sequence.cs)
     * [A057588 Kummer Numbers](./Algorithms/Sequences/KummerNumbersSequence.cs)
     * [A019434 Fermat Primes](./Algorithms/Sequences/FermatPrimesSequence.cs)