my error in the write n!+1 = 0 mod n

3 次查看(过去 30 天)
n=1:500;
n_true = [];
for i=1:length(n)
x = 2:n(i);
nq=factorial(n(i)))+1;
x3 = mod(0,n(i));
if ~any(x3 == nq)
n_true(end+1) = n(i);
end
end
i want find all n values by n!+1 = 0 mod n
  3 个评论
Steven Lord
Steven Lord 2023-3-5
By the definition of the factorial function, factorial(n) is equivalent to 0 mod n as it is n*factorial(n-1). [The base case where n = 0 is handled by the convention, listed on the mod documentation page, that mod(x, 0) is x.] So you're looking for values of n for which 1 is also equivalent to 0 mod n. That would mean 1 is an integer multiple of n. For how many values of n is this true?
Dipankar
Dipankar 2024-6-11
it was tried to found out the solution of Brocards problem

请先登录,再进行评论。

回答(1 个)

Jan
Jan 2023-3-5
编辑:Jan 2023-3-5
nq=factorial(n(i)))+1;
% ^
Here are more closing then opening parentheses.
Whenever you mention an error in the forum, attach a copy of the complete message.
This is strange also:
x3 = mod(0,n(i))
This checks, if 0 is divisable by n(i). Even the equation n!+1 = 0 mod n looks confusing.
  4 个评论
the cyclist
the cyclist 2023-3-5
Of course. Now I feel dumb. Well, dumber than usual. :-)
Mohammed AL Rashedi
Dear the cyclist exactly, "I think he is trying to find n where" .Thank you Walter Roberson .
Thank you guys. I love you

请先登录,再进行评论。

Community Treasure Hunt

Find the treasures in MATLAB Central and discover how the community can help you!

Start Hunting!

Translated by