http://www.jsoftware.com/jwiki/Essays/Fibonacci_Sequence#generating_functions (%-.-*:)t. computes the n-th Fibonacci number. e.g. (%-.-*:)t. 200x 280571172992510140037611932413038677189525
http://www.jsoftware.com/jwiki/Essays/Totient_Function totient=: * [EMAIL PROTECTED]@~.&.q: computes the totient function, the number of numbers less than n which are relatively prime to n . e.g. totient !40x 121343746763281707274905415180804423680000000000 http://www.jsoftware.com/jwiki/Essays/Matrix_Inverse minors =: 1&(|:\.)"2^:2 det =: -/ .* adjoint=: [: |: */~@($&1 _1)@# * [EMAIL PROTECTED] inverse=: adjoint % det compute the inverse of a square matrix. If the requirement is for only one phrase, then "minors" would do. It is the phrase that previously appeared on the green J mug. <"_2 minors i.3 3 +---+---+---+ |4 5|3 5|3 4| |7 8|6 8|6 7| +---+---+---+ |1 2|0 2|0 1| |7 8|6 8|6 7| +---+---+---+ |1 2|0 2|0 1| |4 5|3 5|3 4| +---+---+---+ http://www.jsoftware.com/jwiki/Essays/Ackermann%27s_Function If x ack y is f&.(3&+) y , then (x+1) ack y is f^:(1+y)&.(3&+) 1 ----- Original Message ----- From: June Kim <[EMAIL PROTECTED]> Date: Tuesday, May 15, 2007 9:33 pm Subject: [Jprogramming] the most impressive & beautiful J phrase > Hello, > > I want to design a T-shirt for J programmers and share with our local > J community friends. > > What I'm planning to do is put a few J phrases on the front and back > of the T-shirt, so I'm gathering the phrases. > > What are your favorite, or impressive/beautiful/inspirational phrases > you've seen so far in your J life? > > Thanks in advance. ---------------------------------------------------------------------- For information about J forums see http://www.jsoftware.com/forums.htm
