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a(n) = 12*a(n-2) for n > 2; a(1) = 1, a(2) = 8.
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%I #8 Sep 17 2020 13:54:51

%S 1,8,12,96,144,1152,1728,13824,20736,165888,248832,1990656,2985984,

%T 23887872,35831808,286654464,429981696,3439853568,5159780352,

%U 41278242816,61917364224,495338913792,743008370688,5944066965504

%N a(n) = 12*a(n-2) for n > 2; a(1) = 1, a(2) = 8.

%C Eighth binomial transform is A161729.

%H <a href="/index/Rec#order_02">Index entries for linear recurrences with constant coefficients</a>, signature (0,12).

%F a(n) = (5-(-1)^n)*2^(1/2 *(2*n-3+(-1)^n))*3^(1/4*(2*n-5+(-1)^n)).

%F G.f.: x*(1+8*x)/(1-12*x^2).

%F a(n) = 2^(n-1)*A074324(n). - _M. F. Hasler_, Dec 03 2014

%t LinearRecurrence[{0,12},{1,8},30] (* _Harvey P. Dale_, Sep 17 2020 *)

%o (PARI) {m=24; v=concat([1, 8], vector(m-2)); for(n=3, m, v[n]=12*v[n-2]); v}

%o (PARI) Vec(x*(1+8*x)/(1-12*x^2)+O(x^29)) \\ _M. F. Hasler_, Dec 03 2014

%Y Cf. A161729, A161728, A162436, A162272, A074324.

%K nonn

%O 1,2

%A _Klaus Brockhaus_, Jul 04 2009

%E G.f. and comment corrected, formula added by _Klaus Brockhaus_, Sep 18 2009