Golf Recamán's sequence
3 views (last 30 days)
Show older comments
Recamán's sequence described in pseudo-code is as follows:
A(0) = 0
A(n) = A(n-1) - n if A(n-1) - n > 0 and is new, else
A(n) = A(n-1) + n
The 11 first elements is:
0, 1, 3, 6, 2, 7, 13, 20, 12, 21, 11
As a challenge, I should write a function that outputs the first n elements, in as few characters as possible, where the number of elements to display should be used as input to the function. The best I can do is 90 characters:
function A=f(n)
A=0;for i=1:n-1 b=A(i)-i;A(i+1)=b+2*i;if b>0&&~any(A==b) A(i+1)=b;end;end
(written out):
function A = Recamans(n)
A = zeros(1,n);
A(1) = 0;
for ii = 1:n-1
b = A(ii)-ii;
A(ii+1) = b + 2*ii;
if b > 0 && ~any(A == b)
A(ii + 1) = b;
end
end
end
MY question is: Is it possible to do this in fewer characters in MATLAB?
0 Comments
Answers (1)
George Iskander
on 5 Feb 2020
function x=Recaman_seq(n)
x=zeros(1,n);
for ii=2:length(x)
p=x(ii-1)-ii+1;
if (all(x~=p) && p>0)
x(ii)=p
else
x(ii)=x(ii-1)+ii-1
end
end
0 Comments
See Also
Categories
Find more on Audio and Video Data in Help Center and File Exchange
Community Treasure Hunt
Find the treasures in MATLAB Central and discover how the community can help you!
Start Hunting!