doc-src/Tutorial/Recdef/ack
author paulson
Wed, 14 Feb 2001 12:16:32 +0100
changeset 11115 285b31e9e026
parent 9255 2ceb11a2e190
permissions -rw-r--r--
a new theorem from Bryan Ford

consts ack :: "nat*nat => nat"
recdef ack "measure(%m. m) <*lex*> measure(%n. n)"
  "ack(0,n)         = Suc n"
  "ack(Suc m,0)     = ack(m, 1)"
  "ack(Suc m,Suc n) = ack(m,ack(Suc m,n))"