Contents

describe Integer, "#hexagonal?" do
  # A000384
  HEXAGONAL = [0,1,6,15,28,45,66,91,120,153,190,231,276,325,378,
               435,496,561,630,703,780,861,946,1035,1128,1225,
               1326,1431,1540,1653,1770,1891,2016,2145,2278,2415,
               2556,2701,2850,3003,3160,3321,3486,3655,3828,4005,
               4186,4371,4560]

  it "returns true for a hexagonal number" do
    HEXAGONAL.each{|n| n.should be_hexagonal}
  end

  it "returns false for a non-hexagonal number" do
    ((0..HEXAGONAL.last).to_a - HEXAGONAL).each{|n| n.should_not be_hexagonal}
  end
end

Version data entries

2 entries across 2 versions & 1 rubygems

Version	Path
numb-0.21.0	spec/hexagonal_spec.rb
numb-0.20.0	spec/hexagonal_spec.rb