10001th prime: Difference between revisions

for swi-prolog

<syntaxhighlight lang="prolog">isPrime(2).

isPrime(N):-

between(3, inf, N), % prime generator

N /\ 1 > 0, % odd

M is floor(sqrt(N)) - 1, % reverse 2*I+1

Max is M div 2,

forall(between(1, Max, I), N mod (2*I+1) > 0).

do:- Index is 10001,

findnsols(Index, N, isPrime(N), PrimeList),!,

last(PrimeList, PrimeAtIndex),

format('prime(~w) is ~w', [Index, PrimeAtIndex]), nl.</syntaxhighlight>

<pre>?- do.

prime(10001) is 104743

true.</pre>