First 9 prime Fibonacci number: Difference between revisions
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514229</pre>
=={{header|Delphi}}==
{{works with|Delphi|6.0}}
{{libheader|SysUtils,StdCtrls}}
<syntaxhighlight lang="Delphi">
function IsPrime(N: integer): boolean;
{Fast, optimised prime test}
var I,Stop: integer;
begin
if (N = 2) or (N=3) then Result:=true
else if (n <= 1) or ((n mod 2) = 0) or ((n mod 3) = 0) then Result:= false
else
begin
I:=5;
Stop:=Trunc(sqrt(N));
Result:=False;
while I<=Stop do
begin
if ((N mod I) = 0) or ((N mod (I + 2)) = 0) then exit;
Inc(I,6);
end;
Result:=True;
end;
end;
procedure ShowFibonacciPrimes(Memo: TMemo);
{Find and display first nine Fibonacci primes}
var N1,N2,T,Cnt: integer;
begin
Cnt:=0;
N1:=0; N2:=1;
while true do
begin
{Calculate next Fib number}
T:=N1+N2;
N1:=N2; N2:=T;
{Test if it is prime}
if IsPrime(N2) then
begin
Inc(Cnt);
Memo.Lines.Add(IntToStr(N2));
if Cnt>=9 then break;
end;
end;
end;
</syntaxhighlight>
{{out}}
<pre>
2
3
5
13
89
233
1597
28657
514229
</pre>
=={{header|Draco}}==
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