L's in Circles

The following pictures show n L's with short side 1 packed inside the smallest circle (of radius r).

1.
           2.
           3.
r = √2 = 1.414+
Trivial. 		r = √13/2 = 1.802+
Found by David W. Cantrell
in June 2005. 		r = √305/8 = 2.183+
Found by Maurizio Morandi
in August 2007.

4.
           5.
           6.
r = √5 = 2.236+
Found by Erich Friedman
in June 2005. 		r = 2.569+
Found by Maxim Razin and Nick Baxter
in November 2019. 		r = √8249/32 = 2.838+
Found by Erich Friedman
in June 2005.

7.
           8.
           9.
r = √34/2 = 2.915+
Found by Erich Friedman
in June 2005. 		r = √10 = 3.162+
Found by Erich Friedman
in June 2005. 		r = 3.373+
Found by David W. Cantrell
in August 2007.

10.
           11.
           12.
r = 3.516+
Found by Maurizio Morandi
in August 2007. 		r = 3.705+
Found by Maurizio Morandi
in September 2008. 		r = √58/2 = 3.807+
Found by Erich Friedman
in June 2005.

13.
           14.
           15.
r = 3.958+
Found by Maurizio Morandi
in September 2008. 		r = √17 = 4.123+
Found by David W. Cantrell
in August 2007. 		r = 4.214+
Found by Maurizio Morandi
in August 2007.

16.
           17.
           18.
r = √74/2 = 4.301+
Found by Maurizio Morandi
in September 2008. 		r = 2√5 = 4.472+
Found by Maurizio Morandi
in September 2008. 		r = √86609/64 = 4.598+
Found by Maurizio Morandi
in September 2008.