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diff --git a/exercism/emacs-lisp/difference-of-squares/.exercism/config.json b/exercism/emacs-lisp/difference-of-squares/.exercism/config.json
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+{
+  "blurb": "Find the difference between the square of the sum and the sum of the squares of the first N natural numbers.",
+  "authors": [
+    "canweriotnow"
+  ],
+  "contributors": [
+    "Scientifica96",
+    "vermiculus",
+    "yurrriq"
+  ],
+  "files": {
+    "solution": [
+      "difference-of-squares.el"
+    ],
+    "test": [
+      "difference-of-squares-test.el"
+    ],
+    "example": [
+      ".meta/example.el"
+    ]
+  },
+  "source": "Problem 6 at Project Euler",
+  "source_url": "http://projecteuler.net/problem=6"
+}
diff --git a/exercism/emacs-lisp/difference-of-squares/.exercism/metadata.json b/exercism/emacs-lisp/difference-of-squares/.exercism/metadata.json
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+{"track":"emacs-lisp","exercise":"difference-of-squares","id":"d839accd4cc147648cf015b4a41e496d","url":"https://exercism.org/tracks/emacs-lisp/exercises/difference-of-squares","handle":"orbekk","is_requester":true,"auto_approve":false}
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diff --git a/exercism/emacs-lisp/difference-of-squares/HELP.md b/exercism/emacs-lisp/difference-of-squares/HELP.md
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+# Help
+
+## Running the tests
+
+Tests can be run several ways:
+
+1. Interactively and individually, with `M-x ert RET test-name RET`
+2. Interactively and all at once, with `M-x ert RET t RET`
+3. From the terminal, in batch mode, with `emacs -batch -l ert -l my-test.el -f ert-run-tests-batch-and-exit`
+4. Other options can be found in the docs, `C-h i m ert RET`
+
+## Submitting your solution
+
+You can submit your solution using the `exercism submit difference-of-squares.el` command.
+This command will upload your solution to the Exercism website and print the solution page's URL.
+
+It's possible to submit an incomplete solution which allows you to:
+
+- See how others have completed the exercise
+- Request help from a mentor
+
+## Need to get help?
+
+If you'd like help solving the exercise, check the following pages:
+
+- The [Emacs Lisp track's documentation](https://exercism.org/docs/tracks/emacs-lisp)
+- [Exercism's support channel on gitter](https://gitter.im/exercism/support)
+- The [Frequently Asked Questions](https://exercism.org/docs/using/faqs)
+
+Should those resources not suffice, you could submit your (incomplete) solution to request mentoring.
+
+To get help if you're having trouble, you can use one of the following resources:
+
+- [The Emacs Wiki](http://emacswiki.org/) is invaluable. Spend lots of time here.
+- [The Emacs Editor](http://www.gnu.org/software/emacs/manual/html_node/emacs/index.html) is the official manual for GNU Emacs.
+- IRC - there are [freenode](https://freenode.net/) channels for `#emacs`, `#prelude`, and many Emacs
+  packages, and many helpful folks around. And with emacs, IRC is as close as
+  `M-x erc`.
+- [Exercism Support](https://gitter.im/exercism/support) Gitter chat is also a good place to get help from the
+  exercism community.
+- [StackOverflow](http://stackoverflow.com/questions/tagged/elisp) can be used to search for your problem and see if it has been answered already. You can also ask and answer questions.
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diff --git a/exercism/emacs-lisp/difference-of-squares/README.md b/exercism/emacs-lisp/difference-of-squares/README.md
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+# Difference Of Squares
+
+Welcome to Difference Of Squares on Exercism's Emacs Lisp Track.
+If you need help running the tests or submitting your code, check out `HELP.md`.
+
+## Instructions
+
+Find the difference between the square of the sum and the sum of the squares of the first N natural numbers.
+
+The square of the sum of the first ten natural numbers is
+(1 + 2 + ... + 10)² = 55² = 3025.
+
+The sum of the squares of the first ten natural numbers is
+1² + 2² + ... + 10² = 385.
+
+Hence the difference between the square of the sum of the first
+ten natural numbers and the sum of the squares of the first ten
+natural numbers is 3025 - 385 = 2640.
+
+You are not expected to discover an efficient solution to this yourself from
+first principles; research is allowed, indeed, encouraged. Finding the best
+algorithm for the problem is a key skill in software engineering.
+
+## Source
+
+### Created by
+
+- @canweriotnow
+
+### Contributed to by
+
+- @Scientifica96
+- @vermiculus
+- @yurrriq
+
+### Based on
+
+Problem 6 at Project Euler - http://projecteuler.net/problem=6
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diff --git a/exercism/emacs-lisp/difference-of-squares/difference-of-squares-test.el b/exercism/emacs-lisp/difference-of-squares/difference-of-squares-test.el
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+++ b/exercism/emacs-lisp/difference-of-squares/difference-of-squares-test.el
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+;;; difference-of-squares-test.el --- Tests for difference-of-squares (exercism)
+
+;;; Commentary:
+
+;;; Code:
+
+(load-file "difference-of-squares.el")
+
+(ert-deftest square-of-sum-to-5 ()
+  (should (= 225 (square-of-sum 5))))
+
+(ert-deftest sum-of-squares-to-5 ()
+  (should (= 55 (sum-of-squares 5))))
+
+(ert-deftest difference-of-squares-to-5 ()
+  (should (= 170 (difference 5))))
+
+
+(ert-deftest square-of-sum-to-10 ()
+  (should (= 3025 (square-of-sum 10))))
+
+(ert-deftest sum-of-squares-to-10 ()
+  (should (= 385 (sum-of-squares 10))))
+
+(ert-deftest difference-of-squares-to-10 ()
+  (should (= 2640 (difference 10))))
+
+
+(ert-deftest square-of-sum-to-100 ()
+  (should (= 25502500 (square-of-sum 100))))
+
+(ert-deftest sum-of-squares-to-100 ()
+  (should (= 338350 (sum-of-squares 100))))
+
+(ert-deftest difference-of-squares-to-100 ()
+  (should (= 25164150 (difference 100))))
+
+
+(provide 'difference-of-squares-test)
+;;; difference-of-squares-test.el ends here
diff --git a/exercism/emacs-lisp/difference-of-squares/difference-of-squares.el b/exercism/emacs-lisp/difference-of-squares/difference-of-squares.el
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+++ b/exercism/emacs-lisp/difference-of-squares/difference-of-squares.el
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+;;; difference-of-squares.el --- Difference of Squares (exercism)
+
+;;; Commentary:
+
+;;; Code:
+(require 'cl)
+
+(defun square-of-sum (n)
+  (cl-loop for i from 1 to n
+           sum i into s
+           finally return (* s s)))
+
+(defun sum-of-squares (n)
+  (cl-loop for i from 1 to n
+           sum (* i i)))
+
+(defun difference (n)
+  (- (square-of-sum n) (sum-of-squares n)))
+
+(provide 'difference-of-squares)
+;;; difference-of-squares.el ends here