Complex automatic fill

I have a problem with the automatic fill function when I use complex formulas: I would like to have some of the parameters automatically filled but leave alone some fixed parameters.

For example:
In the column A I have the series 1,2,3,4 in the cells A1,A2,A3,A4
In the cell B1 I have the value of 10
I would like to sum the values of the series in the column A with the cell B1

However, if I use the formula =A1+B1 say in cell C1 and I attempt an automatic fill I have the series A1+B1, A2+B2, A3+B3, A4+B4 and not my desired result (that would be, of course, A1+B1, A2+B1, A3+B1, A4+B1).

Is there a way to have the formulas filled automatically but leaving alone some of the parameters?

=A1+B$1  It's absolute vs. relative addressing.

Great! Thanks a lot

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