I suppose you mean integers, but you don't say....
N = round(randn(1,1000));
S = 0;
maxiter = 2e6;
cnt = 1;
while S~=5 & cnt<maxiter
R = ceil(rand(1,5)*1000);
S = sum(N(R));
cnt = cnt + 1;
end
Now we have the numbers, so look at them:
nums = N(R)
sum(nums)
