From 883c5a6f5d52f53d0eff14575e3e542c0015e8ce Mon Sep 17 00:00:00 2001
From: SpiderMath <71999854+SpiderMath@users.noreply.github.com>
Date: Tue, 13 Dec 2022 08:37:39 +0530
Subject: [PATCH 1/2] =?UTF-8?q?Added=20implementation=20for=20Pronic=20Num?=
 =?UTF-8?q?ber=20=F0=9F=98=81?=
MIME-Version: 1.0
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---
 maths/pronic_number.ts           | 24 ++++++++++++++++++++++++
 maths/test/pronic_number.test.ts |  5 +++++
 2 files changed, 29 insertions(+)
 create mode 100644 maths/pronic_number.ts
 create mode 100644 maths/test/pronic_number.test.ts

diff --git a/maths/pronic_number.ts b/maths/pronic_number.ts
new file mode 100644
index 00000000..3709c6b5
--- /dev/null
+++ b/maths/pronic_number.ts
@@ -0,0 +1,24 @@
+/**
+ * @function PronicNumber
+ * @description Checks whether a given number is a pronic number or not
+ * @summary Pronic numbers, or oblong numbers as they are often referred to as,
+ * are numbers which are the product of two consecutive integers. That is,
+ * they are numbers of the form n*(n+1)
+ * 
+ * For example, 20 is a pronic number since 20 = 4 * 5
+ * @param num The number to check for being pronic
+ * @returns {boolean} Whether the number is pronic or not
+ * @see [Wikipedia](https://en.wikipedia.org/wiki/Pronic_number)
+ * @example PronicNumber(20) = true
+ * @example PronicNumber(30) = true
+ * @example PronicNumber(49) = false
+ */
+const PronicNumber = (n: number) => {
+  if (isNaN(n)) throw new Error('The input needs to be a number')
+  if (!Number.isInteger(n) || n < 0) throw new Error('The input needs to be a non-negative integer')
+  if (n === 0) return true
+
+  return !Number.isInteger(Math.sqrt(n)) && Math.floor(Math.sqrt(n)) * Math.ceil(Math.sqrt(n)) === n
+}
+
+export { PronicNumber }
diff --git a/maths/test/pronic_number.test.ts b/maths/test/pronic_number.test.ts
new file mode 100644
index 00000000..80b5a1fc
--- /dev/null
+++ b/maths/test/pronic_number.test.ts
@@ -0,0 +1,5 @@
+import { PronicNumber } from '../pronic_number'
+
+test.each([[0, true], [10, false], [30, true], [69, false], [420, true]])('Pronic Number', (number, result) => {
+  expect(PronicNumber(number)).toBe(result)
+})

From 0e70cdaabfd867b14c93b2ac05d8a5ecae3a77be Mon Sep 17 00:00:00 2001
From: autoprettier <actions@github.com>
Date: Tue, 13 Dec 2022 03:08:52 +0000
Subject: [PATCH 2/2] Update DIRECTORY.md

---
 DIRECTORY.md | 1 +
 1 file changed, 1 insertion(+)

diff --git a/DIRECTORY.md b/DIRECTORY.md
index 6ad6b372..731d3433 100644
--- a/DIRECTORY.md
+++ b/DIRECTORY.md
@@ -26,6 +26,7 @@
   * [Is Odd](https://github.com/TheAlgorithms/TypeScript/blob/HEAD/maths/is_odd.ts)
   * [Lowest Common Multiple](https://github.com/TheAlgorithms/TypeScript/blob/HEAD/maths/lowest_common_multiple.ts)
   * [Perfect Square](https://github.com/TheAlgorithms/TypeScript/blob/HEAD/maths/perfect_square.ts)
+  * [Pronic Number](https://github.com/TheAlgorithms/TypeScript/blob/HEAD/maths/pronic_number.ts)
   * [Radians To Degrees](https://github.com/TheAlgorithms/TypeScript/blob/HEAD/maths/radians_to_degrees.ts)
   * Series
     * [Hexagonal Numbers](https://github.com/TheAlgorithms/TypeScript/blob/HEAD/maths/series/hexagonal_numbers.ts)