Sha256: c03000a9e7b8a7b4100a5cf5202f53cd72aefce23178fae43a4f0758c2ba62aa
Contents?: true
Size: 335 Bytes
Versions: 20
Compression:
Stored size: 335 Bytes
Contents
class Integer
def congruum?
# Fibonacci proved that h|24
# Fermat’s right triangle theorem shows h is not square
return false unless divides?(24) and not square?
h = self
(1..Math.sqrt(h)).any? do |n|
(n.succ..Math.sqrt(h)).any? do |m|
h == (4 * m * n) * (m**2 - n**2)
end
end
end
end
Version data entries
20 entries across 20 versions & 1 rubygems