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%I #20 Aug 27 2022 14:14:12
%S 0,1,4,6,16,20,48,56,128,144,320,352,768,832,1792,1920,4096,4352,9216,
%T 9728,20480,21504,45056,47104,98304,102400,212992,221184,458752,
%U 475136,983040,1015808,2097152,2162688,4456448,4587520,9437184,9699328,19922944,20447232,41943040,42991616
%N a(n) = n*2^(floor(n/2)).
%H Simon Plouffe, <a href="http://plouffe.fr/Simon%20Plouffe_fichiers/pibase2integerpart.gif">Illustration</a>
%H <a href="/index/Rec#order_04">Index entries for linear recurrences with constant coefficients</a>, signature (0,4,0,-4).
%F G.f.: x*(1 + 4*x + 2*x^2)/(1 - 2*x^2)^2. - _Ilya Gutkovskiy_, Feb 24 2017
%F a(n) = n*A016116(n). - _Michel Marcus_, Feb 17 2018
%p seq(n*2^(floor(n/2)),n=1..120);
%t Table[n*2^Floor[n/2], {n, 0, 100}] (* _Wesley Ivan Hurt_, Dec 12 2013 *)
%t LinearRecurrence[{0,4,0,-4},{0,1,4,6},50] (* _Harvey P. Dale_, Aug 27 2022 *)
%o (PARI) a(n) = n*2^(n\2); \\ _Michel Marcus_, Feb 17 2018
%Y Cf. A004526, A016116.
%K nonn,easy
%O 0,3
%A _Simon Plouffe_, Nov 19 2007
%E More terms from _Michel Marcus_, Feb 17 2018
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