Tupper's selfreferential formula

Link: http://en.wikipedia.org/wiki/Tupper's_self-referential_formula


code(matlab)

% use the symbolic toolbox to represent the big integer k 
k =  sym(['960939379918958884971672962127852754715004339660129306651505519271702802395266424689642842174350' ... 
    '718121267153782770623355993237280874144307891325963941337723487857735749823926629715517173716995' ... 
    '165232890538221612403238855866184013235585136048828693337902491454229288667081096184496091705183' ... 
    '454067827731551705405381627380967602565625016981482083418783163849115590225610003652351370343874' ... 
    '461848378737238198224849863465033159410054974700593138339226497249461751545728366702369745461014' ... 
    '655997933798537483143786841806593422227898388722980000748404719']); 
 
[x,y] = meshgrid(0:1:106, 0:1:16); 
 
% evaluate the tupper formula 
tupper = rem(floor(floor((y+k)/17) .* 2.^(-17*x - rem((y+k), 17))), 2); 
 
% convert from symbolic to Matlab's native double precision 
tupper = double(tupper); 
 
% display it! 
image(fliplr((1-tupper)*255)); 
colormap gray 
axis equal 
 
title('Tupper''s (not-so-)self-referential formula!'); 
set(gca, 'XTick', [], 'YTick', []); 

code(java)

function (x,y) {
  // floor(y/17)  <br/>
  var v = dup(y);
  divInt_(v,17);
  
  //negative exponent of 2, rewritten as a bitwise right shift.    <br/>
  var e = mult(x, k17);
  add_(e, mod(y,k17));
  
  var sh = parseInt(bigInt2str(e,10));
  if (sh>0) {
        rightShift_(v, sh-1);
        //final modulo to recover pixel bit.    <br/>
      mod_(v, k4);
      return greater(v,k1);
  } else {
        //final modulo to recover pixel bit.    <br/>
      mod_(v, k2);
      return greater(v,k0);
  }
}
Plot ranges:
X:[ 0, 105]
Y:[ 960939379918958884971672962127852754715004339660129306651505519271702802395266424689642842174350718121267153782770623355993237280874144307891325963941337723487857735749823926629715517173716995165232890538221612403238855866184013235585136048828693337902491454229288667081096184496091705183454067827731551705405381627380967602565625016981482083418783163849115590225610003652351370343874461848378737238198224849863465033159410054974700593138339226497249461751545728366702369745461014655997933798537483143786841806593422227898388722980000748404719, 960939379918958884971672962127852754715004339660129306651505519271702802395266424689642842174350718121267153782770623355993237280874144307891325963941337723487857735749823926629715517173716995165232890538221612403238855866184013235585136048828693337902491454229288667081096184496091705183454067827731551705405381627380967602565625016981482083418783163849115590225610003652351370343874461848378737238198224849863465033159410054974700593138339226497249461751545728366702369745461014655997933798537483143786841806593422227898388722980000748404735]
原文地址:https://www.cnblogs.com/emituofo/p/2488153.html