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%I #16 Dec 14 2016 15:37:47
%S 1,3,6,15,33,84,203,525,1330,3465,8955,23400,60957,159471,416702,
%T 1090635,2853229,7469052,19548759,51177225,133969386,350730933,
%U 918187991,2403833040,6293218393,16475822139,43134005238
%N "BIK" (reversible, indistinct, unlabeled) transform of 1,2,3,4...
%H Harvey P. Dale, <a href="/A032126/b032126.txt">Table of n, a(n) for n = 1..1000</a>
%H C. G. Bower, <a href="/transforms2.html">Transforms (2)</a>
%H <a href="/index/Rec#order_06">Index entries for linear recurrences with constant coefficients</a>, signature (3,2,-9,2,3,-1).
%F a(2n+1) = 1/2 * [F(4n+1) + F(4n) + F(2n+2) + F(2n)], with F(n) = A000045(n). - _Ralf Stephan_, May 04 2004
%F Empirical G.f.: x*(x^4-5*x^2+1) / ((x^2-3*x+1)*(x^2-x-1)*(x^2+x-1)). - _Colin Barker_, Dec 15 2012
%t LinearRecurrence[{3,2,-9,2,3,-1},{1,3,6,15,33,84},30] (* _Harvey P. Dale_, Dec 14 2016 *)
%K nonn
%O 1,2
%A _Christian G. Bower_