http://projecteuler.net/problem=53

**Combinatoric selections**

There are exactly ten ways of selecting three from five, 12345:

123, 124, 125, 134, 135, 145, 234, 235, 245, and 345

In combinatorics, we use the notation,^{5}C_{3}= 10.

where r n, n! = n(n1)…321, and 0! = 1.How many, not necessarily distinct, values of

^{n}C_{r}, for 1n100, are greater than one-million?

Does this count as solution a for this problem?

value = 12345

result = value.to_s.scan(/.{1,1}/).combination(3).to_a.map { |e| e.join.to_i }

p result

Partially, yes.