There are a batch of steel pipes stored in a certain warehouse, which are stacked layer by layer in a trapezoidal shape. There are 5 steel pipes in the top layer, and there are 1 more steel pipes in the lower layer than the upper layer. There are 7 layers in total. How many steel pipes are there in this batch?
某仓库存一批钢管，一层一层地堆成梯形，最上一层有5根钢管，下边的一层总比上边一层多1根，共有7层，这批钢管，共有多少根？
<gadget id="calculator">5 + 1 + 1 + 1 + 1 + 1 + 1</gadget>
<output>11</output>

<gadget id="calculator">5 + 11</gadget>
<output>16</output>

<gadget id="calculator">7 / 2</gadget>
<output>7/2 = around 3.5</output>

<gadget id="calculator">16 * (7/2)</gadget>
<output>56</output>

<result>56</result>