Using your Head is Permitted

June 2013 riddle

This month's riddle continues last month's IBM Ponder This riddle. (Thank you puzzlemaster Oded Margalit for another wonderful cooperation.)

The original riddle defined a function:

f(x) = 1+x+x2+x4 (modulo 2233393)

and requested solvers to compute it using addition, multiplication and modulo operations, with some restrictions on how multiplication can be used. (Readers are directed to the original riddle for the complete details.)

This month, we make the riddle slightly more difficult, as follows:

  1. Multiplication is not allowed at all.
  2. The total number of operations used should be at most 10.

To be considered a solver, please send in your program.

Good luck!

List of solvers:

Yuping Luo: 4 operations (4 June 10:47)
Radu-Alexandru Todor: 4 operations (6 June 06:38)
Jan Fricke: 4 operations (9 June 07:13)
Haoqiang Fan: 4 operations (12 June 19:11)
Dharmadeep Muppalla: 4 operations (13 June 04:03)
Lorenzo Gianferrari Pini: 4 operations (21 June 19:59)

Elegant and original solutions can be submitted to the puzzlemaster at Names of solvers will be posted on this page. Notify if you don't want your name to be mentioned.

The solution will be published at the end of the month.


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