From 6ac91086cd8434a5bc6321bd0170bb935aaa9c3a Mon Sep 17 00:00:00 2001
From: neumannth67917 <neumannth67917@th-nuernberg.de>
Date: Wed, 15 Jul 2020 13:33:45 +0200
Subject: [PATCH] Add explanation for sieve of eratosthenes
---
.gitignore | 1 +
Main.hs | 2 +-
TheSieveOfEratosthenes.md | 18 ++++++++++++++++++
3 files changed, 20 insertions(+), 1 deletion(-)
create mode 100644 TheSieveOfEratosthenes.md
diff --git a/.gitignore b/.gitignore
index b09d2bf..154f851 100644
--- a/.gitignore
+++ b/.gitignore
@@ -1,5 +1,6 @@
# Own:
*.exe
+.idea
# From https://raw.githubusercontent.com/github/gitignore/master/Haskell.gitignore
dist
diff --git a/Main.hs b/Main.hs
index 7d4ab60..95af32f 100644
--- a/Main.hs
+++ b/Main.hs
@@ -1,3 +1,3 @@
import SieveOfEratosthenes
-main = putStrLn (show (take 10 (primes) ) )
+main = putStrLn ("First 9 prime numbers: " ++ (show (take 9 (primes) ) ) )
diff --git a/TheSieveOfEratosthenes.md b/TheSieveOfEratosthenes.md
new file mode 100644
index 0000000..803e8b1
--- /dev/null
+++ b/TheSieveOfEratosthenes.md
@@ -0,0 +1,18 @@
+# The Sieve of Eratosthenes
+
+1. Write down the successive "plurals": 2, 3, 4, ...
+2. Repeat:
+ 1. Take the first number that is not circled or crossed out.
+ 2. Circle it.
+ 3. Cross out its proper multiples.
+3. What is left (i.e. the circled numbers) are the successive prime numbers.
+
+**Example**
+
+```
+ 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 ...
+(2) 3 x 5 x 7 x 9 xx 11 xx 13 xx 15 xx 17 xx 19 xx 21 xx 23 xx 25 ...
+(2) (3) 5 7 x 11 13 xx 17 19 xx 23 25 ...
+(2) (3) (5) 7 11 13 17 19 23 xx ...
+...
+```
--
GitLab