Fixed points of A374941.

Terms

a(0) =12a(1) =30a(2) =80a(3) =324a(4) =448a(5) =888a(6) =11264a(7) =53248a(8) =1114112a(9) =3684352a(10) =4980736a(11) =18055168a(12) =96468992