MATLAB: How to check if a specific set of numbers are present in the array

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Let I have a 1D array A of real positive increasing integers of length N. I want to check if the elements in it have natural order (and not missing any natural number). let me explain it with exampls:
Example 1:
A = [ 2 5 7 8 9 14 16]
there are 3 ordered numbers from 7 to 9, [7 8 9]. I want to write a code which can show me these numbers.
Example 2:
B = [ 1 4 5 6 7 8 10 11 12 16 20 ]
in this array there are two ordered set of numbers, one [4 5 6 7 8] and other is [10 11 12]. I want my code to display both of them. hmm… I want to have power to decide the minimum length of ordered numbers.
Example 3 (final):
C = [ 1 2 3 4 5 11 14 15 16 17 18 22 25 26 30 31 32]
Let I say that minimum length to choose ordered number is 3 then, there are three such pairs in C, [1 2 3 4 5], [14 15 16 17 18] and [30 31 32].
Hope I have made my question clear.

Best Answer

In this solution, the vector C is differentiated and then we find the starting point of each consecutive segment of 1s using bwlabel() (image processing toolbox). The rest is pretty much straight forward. I'm not sure what you're going to do with these consecutive segments but I've stored them in a cell array 'consecs' and put them into a table 'T' to show you how you pull them out of the vector C and display their start/end indices. Set the variable 'm' to the minimum length of consecutive numbers accepted. 
C = [ 1 2 3 4 5 11 14 15 16 17 18 22 25 26 30 31 32]; 
m = 3; % minimum length of consecutive numbers
% Identify the start/end index of all consecutive numbers
dC = bwlabel(diff(C)==1);  % requires image processing toolbox
startIdx = arrayfun(@(x) find(dC == x,1), unique(dC));
endIdx = arrayfun(@(x,y)sum(dC == x)+y, unique(dC), startIdx);
% Get rid of start/stop indices of length '0' (they are meaningless)
startIdx(unique(dC)==0) = []; 
endIdx(unique(dC)==0) = []; 
% get rid of any that are below the minimum length
len = endIdx - startIdx +1; 
startIdx(len < m) = []; 
endIdx(len < m) = []; 
% Pull out the consecutive numbers have have a length equal to or greater than m
consecs = arrayfun(@(x,y) C(x):C(y), startIdx, endIdx, 'UniformOutput', false)'; 
% Show results in a table
T = table(startIdx', endIdx', consecs, 'VariableNames', {'StartIndex', 'StopIndex', 'Consecs'})
And the result
T = 
3×3 table
    StartIndex    StopIndex      Consecs   
    __________    _________    ____________
         1            5        [1×5 double]
         7           11        [1×5 double]
        15           17        [1×3 double]
        
>> T.Consecs{1}
ans =
     1     2     3     4     5
>> T.Consecs{2}
ans =
    14    15    16    17    18
>> T.Consecs{3}
ans =
    30    31    32
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