%N Fractal-jump sequence (FJS) based on Pi.
%e Start on the first digit (3), underline it and jump over the next 3 digits; you land on (1) which you underline and leave by jumping over 1 digit; you land on (4) which you underline and leave by jumping over the next 4 digits; you land on (1) which you underline and leave by jumping jump over 1 digit; you land on (5) etc. The underlined digits show the decimal expansion of Pi. If you now erase all those underlined digits the resulting sequence is the one you started with. [To jump over "0" digit means moving to the next digit on the right, of course]
%A _Eric Angelini_, May 13 2005