{ "items" : [
    { "id" : "http://dbpedia.org/resource/Ordinal_arithmetic"
      "properties" : {
        "http://www.w3.org/2000/01/rdf-schema#comment" : [ "In the mathematical field of set theory, ordinal arithmetic describes the three usual operations on ordinal numbers: addition, multiplication, and exponentiation.  Each can be defined in essentially two different ways: either by constructing an explicit well-ordered set which represents the operation or by using transfinite recursion.  Cantor normal form provides a standardized way of writing ordinals."] } } }
