diff --git a/semana23/exercicios-aula74/README.md b/semana23/exercicios-aula74/README.md
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+++ b/semana23/exercicios-aula74/README.md
@@ -0,0 +1,38 @@
+### Exerícios aula 74
+## 1.a
+~~~typescript
+const exercice1=(n: number): void=>{
+  if(n >= 0){
+    exercice1(n-1)
+    console.log(n)
+  }
+}
+~~~
+## 1.b
+~~~typescript
+const exercice1=(n: number): void=>{
+  if(n >= 0){
+    console.log(n)
+    exercice1(n-1)
+  }
+}
+~~~
+## 2.
+~~~typescript
+const exercice2=(n: number): number=>{
+  if(n <= 1 ){
+    return 1
+  }
+  return exercice2(n-1) + n
+}
+~~~
+## 3.
+~~~typescript
+const exercice3=(array: any[], index = 0): void =>{
+  if(index < array.length){
+    console.log(array[index])
+    index ++
+    exercice3(array, index)
+  }
+}
+~~~
\ No newline at end of file
diff --git a/semana23/exercicios-aula74/package-lock.json b/semana23/exercicios-aula74/package-lock.json
new file mode 100644
index 0000000..320802b
--- /dev/null
+++ b/semana23/exercicios-aula74/package-lock.json
@@ -0,0 +1,69 @@
+{
+  "name": "exercicios-aula74",
+  "version": "1.0.0",
+  "lockfileVersion": 1,
+  "requires": true,
+  "dependencies": {
+    "@types/node": {
+      "version": "14.6.0",
+      "resolved": "https://registry.npmjs.org/@types/node/-/node-14.6.0.tgz",
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+    },
+    "arg": {
+      "version": "4.1.3",
+      "resolved": "https://registry.npmjs.org/arg/-/arg-4.1.3.tgz",
+      "integrity": "sha512-58S9QDqG0Xx27YwPSt9fJxivjYl432YCwfDMfZ+71RAqUrZef7LrKQZ3LHLOwCS4FLNBplP533Zx895SeOCHvA=="
+    },
+    "buffer-from": {
+      "version": "1.1.1",
+      "resolved": "https://registry.npmjs.org/buffer-from/-/buffer-from-1.1.1.tgz",
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+    },
+    "diff": {
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+      "resolved": "https://registry.npmjs.org/diff/-/diff-4.0.2.tgz",
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+    },
+    "make-error": {
+      "version": "1.3.6",
+      "resolved": "https://registry.npmjs.org/make-error/-/make-error-1.3.6.tgz",
+      "integrity": "sha512-s8UhlNe7vPKomQhC1qFelMokr/Sc3AgNbso3n74mVPA5LTZwkB9NlXf4XPamLxJE8h0gh73rM94xvwRT2CVInw=="
+    },
+    "source-map": {
+      "version": "0.6.1",
+      "resolved": "https://registry.npmjs.org/source-map/-/source-map-0.6.1.tgz",
+      "integrity": "sha512-UjgapumWlbMhkBgzT7Ykc5YXUT46F0iKu8SGXq0bcwP5dz/h0Plj6enJqjz1Zbq2l5WaqYnrVbwWOWMyF3F47g=="
+    },
+    "source-map-support": {
+      "version": "0.5.19",
+      "resolved": "https://registry.npmjs.org/source-map-support/-/source-map-support-0.5.19.tgz",
+      "integrity": "sha512-Wonm7zOCIJzBGQdB+thsPar0kYuCIzYvxZwlBa87yi/Mdjv7Tip2cyVbLj5o0cFPN4EVkuTwb3GDDyUx2DGnGw==",
+      "requires": {
+        "buffer-from": "^1.0.0",
+        "source-map": "^0.6.0"
+      }
+    },
+    "ts-node": {
+      "version": "9.0.0",
+      "resolved": "https://registry.npmjs.org/ts-node/-/ts-node-9.0.0.tgz",
+      "integrity": "sha512-/TqB4SnererCDR/vb4S/QvSZvzQMJN8daAslg7MeaiHvD8rDZsSfXmNeNumyZZzMned72Xoq/isQljYSt8Ynfg==",
+      "requires": {
+        "arg": "^4.1.0",
+        "diff": "^4.0.1",
+        "make-error": "^1.1.1",
+        "source-map-support": "^0.5.17",
+        "yn": "3.1.1"
+      }
+    },
+    "typescript": {
+      "version": "4.0.2",
+      "resolved": "https://registry.npmjs.org/typescript/-/typescript-4.0.2.tgz",
+      "integrity": "sha512-e4ERvRV2wb+rRZ/IQeb3jm2VxBsirQLpQhdxplZ2MEzGvDkkMmPglecnNDfSUBivMjP93vRbngYYDQqQ/78bcQ=="
+    },
+    "yn": {
+      "version": "3.1.1",
+      "resolved": "https://registry.npmjs.org/yn/-/yn-3.1.1.tgz",
+      "integrity": "sha512-Ux4ygGWsu2c7isFWe8Yu1YluJmqVhxqK2cLXNQA5AcC3QfbGNpM7fu0Y8b/z16pXLnFxZYvWhd3fhBY9DLmC6Q=="
+    }
+  }
+}
diff --git a/semana23/exercicios-aula74/package.json b/semana23/exercicios-aula74/package.json
new file mode 100644
index 0000000..595c15b
--- /dev/null
+++ b/semana23/exercicios-aula74/package.json
@@ -0,0 +1,17 @@
+{
+  "name": "exercicios-aula74",
+  "version": "1.0.0",
+  "description": "exercicios da aula 74, da semana 23",
+  "main": "index.js",
+  "scripts": {
+    "test": "echo \"Error: no test specified\" && exit 1",
+    "start": "clear && ts-node ./src/index.ts"
+  },
+  "author": "OsmanRodrigues",
+  "license": "ISC",
+  "dependencies": {
+    "@types/node": "^14.6.0",
+    "ts-node": "^9.0.0",
+    "typescript": "^4.0.2"
+  }
+}
diff --git a/semana23/exercicios-aula74/src/index.ts b/semana23/exercicios-aula74/src/index.ts
new file mode 100644
index 0000000..642a95e
--- /dev/null
+++ b/semana23/exercicios-aula74/src/index.ts
@@ -0,0 +1,24 @@
+const exercice1=(n: number): void=>{
+  if(n >= 0){
+    console.log(n)
+    exercice1(n-1)
+  }
+}
+
+const exercice2=(n: number): number=>{
+  if(n <= 1 ){
+    return 1
+  }
+
+  return exercice2(n-1) + n
+}
+
+const exercice3=(array: any[], index = 0): void =>{
+  if(index < array.length){
+    console.log(array[index])
+    index ++
+    exercice3(array, index)
+  }
+}
+
+exercice3(['a','b','c', 'd'])
\ No newline at end of file
diff --git a/semana23/exercicios-aula74/tsconfig.json b/semana23/exercicios-aula74/tsconfig.json
new file mode 100644
index 0000000..2bfbb23
--- /dev/null
+++ b/semana23/exercicios-aula74/tsconfig.json
@@ -0,0 +1,14 @@
+{
+  "compilerOptions": {
+    "noImplicitAny": true,
+    "removeComments": true,
+    "preserveConstEnums": true,
+    "outDir": "build",
+    "sourceMap": true,
+    "target": "es6",
+    "module": "commonjs",
+    "esModuleInterop": true
+  },
+  "include": ["src/**/*"],
+  "exclude": ["node_modules"]
+}
\ No newline at end of file