Blum integer: Difference between revisions

</pre>

=={{header|XPL0}}==

Simple minded brute force takes 93 seconds on Pi4.

<syntaxhighlight lang "XPL0">int Prime1;

func Semiprime(N); \Return 'true' if N is semiprime

int N, F, C;

[C:= 0; F:= 2;

repeat if rem(N/F) = 0 then

[C:= C+1;

Prime1:= N;

N:= N/F;

]

else F:= F+1;

until F > N;

return C = 2;

];

int N, C, Prime2;

[Format(4,0);

N:= 3; C:= 0;

loop [if Semiprime(N) then

[if rem(Prime1/4) = 3 then

[Prime2:= N/Prime1;

if Prime2 # Prime1 and rem(Prime2/4) = 3 then

[C:= C+1;

if C <= 50 then

[RlOut(0, float(N));

if rem(C/10) = 0 then CrLf(0);

];

if rem(C/1000)=0 then ChOut(0, ^.);

if C >= 26828 then

[Text(0, "^m^jThe 26828th Blum integer is: ");

IntOut(0, N); CrLf(0);

quit;

];

];

];

];

N:= N+2;

];

]</syntaxhighlight>

{{out}}

<pre>

21 33 57 69 77 93 129 133 141 161

177 201 209 213 217 237 249 253 301 309

321 329 341 381 393 413 417 437 453 469

473 489 497 501 517 537 553 573 581 589

597 633 649 669 681 713 717 721 737 749

..........................

The 26828th Blum integer is: 524273