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%I #23 Sep 08 2022 08:44:50
%S 6,20,72,272,1056,4160,16512,65792,262656,1049600,4196352,16781312,
%T 67117056,268451840,1073774592,4295032832,17180000256,68719738880,
%U 274878431232,1099512676352,4398048608256,17592190238720,70368752566272,281474993487872,1125899940397056
%N Number of types of Boolean functions of n variables under a certain group.
%H Vincenzo Librandi, <a href="/A028402/b028402.txt">Table of n, a(n) for n = 2..300</a>
%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.
%H <a href="/index/Bo#Boolean">Index entries for sequences related to Boolean functions</a>
%H <a href="/index/Rec#order_02">Index entries for linear recurrences with constant coefficients</a>, signature (6,-8).
%F a(n) = 2^(n-1) * (2^(n-1)+1). - _Sean A. Irvine_, Jan 07 2020
%F From _Chai Wah Wu_, Dec 29 2021: (Start)
%F a(n) = 6*a(n-1) - 8*a(n-2) for n > 3.
%F G.f.: x^2*(6 - 16*x)/((2*x - 1)*(4*x - 1)). (End)
%t Table[2^(n-1) (2^(n-1) + 1), {n, 2, 30}] (* _Vincenzo Librandi_, Jan 08 2020 *)
%o (Magma) [2^(n-1)*(2^(n-1)+1): n in [2..30]]; // _Vincenzo Librandi_, Jan 08 2020
%Y Essentially the same as A063376.
%K nonn
%O 2,1
%A _N. J. A. Sloane_.
%E a(6) corrected and more terms from _Sean A. Irvine_, Jan 07 2020
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