title: Calculate SUM without Adding Values to Rows/Columns?
body: <p>When calculating series in Excel, most tutorials begin by setting sequence values to certain range of cells, say</p>
  
  <pre><code> A1=1, A2=2, A3=3,..., A10=10
  </code></pre>
  
  <p>and to get the value of 1+2+...+10, execute</p>
  
  <pre><code> A11=SUM(A1:A10)
  </code></pre>
  
  <p>But I don't want the "generate the sequence in worksheet cells first" part because initially I don't know the 'n' (10 in the above) and I want to define a custom function that takes n as a function argument.</p>
  
  <p>So, is there a way to do something like this?</p>
  
  <pre><code>B1 = SUM([1:10])  // adding array of 'constants', not cell reference
  </code></pre>
  
  <p>EDIT: If I could 'summon' some (array of) big number(s) without any cell/ROW/COL operation as in calling rand(), that would be great.</p>