4 files changed, 117 insertions, 0 deletions
diff --git a/challenge-109/lance-wicks/elm/elm.json b/challenge-109/lance-wicks/elm/elm.json
new file mode 100644
index 0000000000..418d33c9ab
--- /dev/null
+++ b/challenge-109/lance-wicks/elm/elm.json
@@ -0,0 +1,26 @@
+{
+    "type": "application",
+    "source-directories": [
+        "src"
+    ],
+    "elm-version": "0.19.1",
+    "dependencies": {
+        "direct": {
+            "elm/browser": "1.0.2",
+            "elm/core": "1.0.5",
+            "elm/html": "1.0.0",
+            "elm-explorations/test": "1.2.2"
+        },
+        "indirect": {
+            "elm/json": "1.1.3",
+            "elm/random": "1.0.0",
+            "elm/time": "1.0.0",
+            "elm/url": "1.0.0",
+            "elm/virtual-dom": "1.0.2"
+        }
+    },
+    "test-dependencies": {
+        "direct": {},
+        "indirect": {}
+    }
+}
diff --git a/challenge-109/lance-wicks/elm/src/Chowla.elm b/challenge-109/lance-wicks/elm/src/Chowla.elm
new file mode 100644
index 0000000000..d5041545ea
--- /dev/null
+++ b/challenge-109/lance-wicks/elm/src/Chowla.elm
@@ -0,0 +1,31 @@
+module Chowla exposing (chowla, n, nums)
+
+import List
+
+
+nums : Int -> List Int
+nums max =
+    List.range 1 max
+        |> List.map n
+
+
+n : Int -> Int
+n num =
+    let
+        denominators =
+            List.range 2 (num - 1)
+
+        numbers =
+            List.map (chowla num) denominators
+    in
+    List.foldl (+) 0 numbers
+
+
+chowla : Int -> Int -> Int
+chowla num denom =
+    case remainderBy denom num of
+        0 ->
+            denom
+
+        _ ->
+            0
diff --git a/challenge-109/lance-wicks/elm/tests/N.elm b/challenge-109/lance-wicks/elm/tests/N.elm
new file mode 100644
index 0000000000..6a81cde5a1
--- /dev/null
+++ b/challenge-109/lance-wicks/elm/tests/N.elm
@@ -0,0 +1,41 @@
+module N exposing (..)
+
+import Chowla
+import Expect
+import Test exposing (..)
+
+
+suite : Test
+suite =
+    describe "Chowla number"
+        [ test "n 1" <|
+            \_ -> Chowla.n 1 |> Expect.equal 0
+        , test "n 4" <|
+            \_ -> Chowla.n 4 |> Expect.equal 2
+        , test "n 6" <|
+            \_ -> Chowla.n 6 |> Expect.equal 5
+        ]
+
+
+chowla : Test
+chowla =
+    describe "Chowla number logic"
+        [ test "chowla 2 2" <|
+            \_ -> Chowla.chowla 2 2 |> Expect.equal 2
+        , test "chowla 2 3" <|
+            \_ -> Chowla.chowla 2 3 |> Expect.equal 0
+        , test "chowla 2 4" <|
+            \_ -> Chowla.chowla 2 4 |> Expect.equal 0
+        ]
+
+
+list : Test
+list =
+    describe "First 20 Chowla numbers"
+        [ test "nums 6" <|
+            \_ -> Chowla.nums 6 |> Expect.equal [ 0, 0, 0, 2, 0, 5 ]
+        , test "nums 22" <|
+            \_ -> Chowla.nums 22 |> Expect.equal [ 0, 0, 0, 2, 0, 5, 0, 6, 3, 7, 0, 15, 0, 9, 8, 14, 0, 20, 0, 21, 10, 13 ]
+        , test "nums 20" <|
+            \_ -> Chowla.nums 20 |> Expect.equal [ 0, 0, 0, 2, 0, 5, 0, 6, 3, 7, 0, 15, 0, 9, 8, 14, 0, 20, 0, 21 ]
+        ]
diff --git a/challenge-109/lance-wicks/elm/tests/Nums.elm b/challenge-109/lance-wicks/elm/tests/Nums.elm
new file mode 100644
index 0000000000..8fc89e54b8
--- /dev/null
+++ b/challenge-109/lance-wicks/elm/tests/Nums.elm
@@ -0,0 +1,19 @@
+module Nums exposing (..)
+
+import Chowla
+import Expect
+import Test exposing (..)
+
+
+suite : Test
+suite =
+    describe "Chowla numbers"
+        [ test "nums 20" <|
+            \_ -> Chowla.nums 20 |> Expect.equal [ 0, 0, 0, 2, 0, 5, 0, 6, 3, 7, 0, 15, 0, 9, 8, 14, 0, 20, 0, 21 ]
+        , test "nums 18" <|
+            \_ -> Chowla.nums 18 |> Expect.equal [ 0, 0, 0, 2, 0, 5, 0, 6, 3, 7, 0, 15, 0, 9, 8, 14, 0, 20 ]
+        , test "nums 6" <|
+            \_ -> Chowla.nums 6 |> Expect.equal [ 0, 0, 0, 2, 0, 5 ]
+        , test "nums 4" <|
+            \_ -> Chowla.nums 4 |> Expect.equal [ 0, 0, 0, 2 ]
+        ]