Sha256: d04948ea45b40616579b13332ac2fd243c97fb2ff74ee10b9facb1115dd7f5a6
Contents?: true
Size: 360 Bytes
Versions: 20
Compression:
Stored size: 360 Bytes
Contents
class Integer
def leonardo?
n = self
return 1 if n <= 1
phi = Hash[[:+, :-].map{|sign| [sign, (1.send(sign, Math.sqrt(5)) / 2) ]}]
divisor = phi[:+] - phi[:-]
(1..n).any? do |m|
sum = ((2 * ( ( phi[:+]**(m+1) - phi[:-]**(m+1) ).fdiv( divisor ) )) - 1)
return false unless sum.finite?
sum.floor == self
end
end
end
Version data entries
20 entries across 20 versions & 1 rubygems