99 Bottles of Beer
19thAbundant Numbers
27thChristmas Trees
27thDivisors
29thEmirp Numbers
20thEvil Numbers
38thFibonacci
64thFizz Buzz
138thLeap Years
42ndMorse Decoder
9thMorse Encoder
8thNiven Numbers
24thOdious Numbers
34thOrdinal Numbers
23rdPascalβs Triangle
20thPrime Numbers
24thRoman to Arabic
23rdSeven Segment
18thΟ
29th