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%I #19 Sep 08 2022 08:44:50
%S 1,2,720,87178291200,265252859812191058636308480000000,
%T 31469973260387937525653122354950764088012280797258232192163168247821107200000000000000
%N a(n) = (2^n-2)!.
%H I. Strazdins, <a href="https://doi.org/10.1023/A:1005769927571">Universal affine classification of Boolean functions</a>, Acta Applic. Math. 46 (1997), 147-167.
%t Table[(2^n - 2)!, {n, 7}] (* _Vincenzo Librandi_, Jan 05 2020 *)
%o (PARI) a(n) = (2^n-2)!; \\ _Michel Marcus_, Jan 04 2020
%o (Magma) [Factorial(2^n-2): n in [1..7]]; // _Vincenzo Librandi_, Jan 05 2020
%Y Cf. A028366.
%K nonn
%O 1,2
%A _N. J. A. Sloane_
%E Offset corrected by _Sean A. Irvine_, Jan 03 2020