From 6291431b49fc853e44277b1c78cd25315211a63d Mon Sep 17 00:00:00 2001
From: Run Paint Run Run <runrun@runpaint.org>
Date: Wed, 17 Mar 2010 04:35:25 +0000
Subject: [PATCH] Integer#gnomonic?: Add

---
 lib/numb/gnomonic.rb       |  4 ++++
 spec/numb/gnomonic_spec.rb | 21 +++++++++++++++++++++
 2 files changed, 25 insertions(+)
 create mode 100644 lib/numb/gnomonic.rb
 create mode 100644 spec/numb/gnomonic_spec.rb

diff --git a/lib/numb/gnomonic.rb b/lib/numb/gnomonic.rb
new file mode 100644
index 0000000..0740c32
--- /dev/null
+++ b/lib/numb/gnomonic.rb
@@ -0,0 +1,4 @@
+# coding: utf-8
+class Integer
+  alias :gnomonic? :odd?
+end
diff --git a/spec/numb/gnomonic_spec.rb b/spec/numb/gnomonic_spec.rb
new file mode 100644
index 0000000..b6ed427
--- /dev/null
+++ b/spec/numb/gnomonic_spec.rb
@@ -0,0 +1,21 @@
+# coding: utf-8
+describe Integer, "#gnomonic?" do
+  # A005408
+  @seq = [1,3,5,7,9,11,13,15,17,19,21,23,25,27,29,31,33,35,
+          37,39,41,43,45,47,49,51,53,55,57,59,61,63,65,67,
+          69,71,73,75,77,79,81,83,85,87,89,91,93,95,97,99,
+          101,103,105,107,109,111,113,115,117,119,121,123,
+          125,127,129,131]
+
+  @seq.each do |n|
+    it "returns true for gnomonic number #{n}" do
+      n.should be_gnomonic
+    end
+  end
+
+  @seq.to_seq.invert.each do |n|
+    it "returns false for non-gnomonic number #{n}" do
+      n.should_not be_gnomonic
+    end
+  end
+end