doc-src/Tutorial/Recdef/ack
author paulson
Wed, 28 Jul 1999 13:55:34 +0200
changeset 7123 4ab38de3fd20
parent 6100 40d66bc3e83f
child 9255 2ceb11a2e190
permissions -rw-r--r--
congruence rule for |-, etc.

consts ack :: "nat*nat => nat"
recdef ack "measure(%m. m) ** 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))"