% Matlab
% a(1) = 1, a(n)=a(n-1)-p(p(n))-p(n-1) if new and >0, else a(n)=a(n-1)+p(p(n))-p(n-1), where p(n) = n-th prime.

% The highest prime to be found
m=1366747; %1366747 for 10000 terms
p = primes(m);
n = length(p);
a = zeros(1,n);
a(1) = 1;

for i = 2:n
    if p(i) > length(p)
        a = a(1:i-1);
        break
    end
    b = a(i-1) - p(p(i)) - p(i-1);
    if ismember(b, a(1:i-1)) || b<0
        a(i) = a(i-1) + p(p(i)) - p(i-1);
    else
        a(i) = a(i-1) - p(p(i)) - p(i-1);
    end
end

% plot data
figure
scatter(1:length(a),a,'.')
title('A328225 ');
ylabel('A328225(n)');
xlabel('n')

% write b-file

number = 1:10000;
data = [number; a];
fid = fopen('b328225.txt','w');
fprintf(fid,'%d %d \n',data);
fclose(fid);