It is incredible that this thread is so long with answers that are far away from the OP's. The OP's code is just fine, you need a slight modification to get exactly what you need:

Catch[Do[If[IntegerQ[21/i],Throw[i]],{i,2,7,1}];"no solution"]

and will not do more evaluations than necessary... It either find the first integer that divides 21, if not in range "no solution" will be returned.

I agree that a solution using SelectFirst, FirstPosition, FirstCase might be more 'Wolframian' indeed; but if the OP wants to go the Catch/Throw route--which is not too bad actually--, he can, and quite easily. Moreover I was not sure what version the OP uses; SelectFirst and friends are relatively new...

You can actually give a third argument to SelectFirst in the case it is missing, e.g.:

SelectFirst[Range[2, 7], IntegerQ[11/#] &, "no solution"]

Hans,

What follows is not very interesting, but just another example of how to skin the same old cat:

In[1]:= DeleteDuplicates@Table[If[IntegerQ[21/i], i, {}], {i, 2, 7, 1}] /. {} -> "No Solution"

Out[1]= {"No Solution", 3, 7}

Is this what you want? Maybe the Print does not produce exportable data...

Table[ If[Mod[21, i] == 0, {i, "integer"}, {"no integer"}], {i, 2, 7}]

Sir, Can you help on the following? I use the below wolfram code which gives an output={3}.

Catch[Do[If[IntegerQ[21/i],Throw[i]],{i,2,7,1}]].

But, If I use instead a number like ,11, I will get no output at all (Wolfram does not show any output at all). I would like to see an output that shows a message that there is no solution such as: output=NO SOLUTION. Is it possible?. Thanks for your reply. Thanks for your time. LOUIS. ___________

Sir, Thank you very much for your help and time Yours very truly LOUIS ________

Flatten removes the {} elements in the list returned by Table. So there is then nothing to replace. If you omit Flatten, your example seems to work:

In[1]:= Table[If[IntegerQ[21/i], i, {}], {i, 2, 7, 1}] /. {} -> "No Solution"

Out[1]= {"No Solution", 3, "No Solution", "No Solution", "No Solution", 7}

Sir, Madam, Thanks for your help. The code you provided runs well but it is not exactly what I am looking for.

First exercice, I want to transfer the total output (using the exact initial code you have provided) into an excel file. I have used table=........... then Export["ExcelTest.xlsx, table]. The table is created but the data do not transfer. Can you tell me why? Notice the extension of the file is .xlsx (excel 2016) and not .xls

Second exercice, I want the output corresponding only to the results such 3{integer} and 7{integer} BUT if there is not an integer I want the output to be only showing a result such as {no integer at all}. How do you transform your initial code?

Thanks for your help again, _______________

Sir, Your solution was quite interesting but the output is too heavy for me. It gives all results along with "Integer" or "not an integer"

Do[Print[{21/i, If[IntegerQ[21/i], "integer", "not an integer"]}], {i,   2, 7, 1}]

But I am looking for the following: If the input gives a result, I Print only the integer and maybe only the first integer I catch up But If the input does not give any result, such as

Do[Print[{21/i, If[IntegerQ[21/i], "integer", "not an integer"]}], {i,   2, 5, 1}] 

I only want to print an output such as "No Solution" Is it possible to make so? Thanks for your reply Louis __________