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%I #5 Jul 26 2022 12:04:51
%S 0,0,0,0,1,4,12,32,78,180,400,864,1827,3800,7800,15840,31884,63704,
%T 126480,249760,490885,960828,1873828,3642560,7060314,13649196,
%U 26324704,50662464,97309767,186571248,357119472,682524224,1302589016,2482706544
%N Number of binary sequences of length n containing exactly one subsequence 0011.
%C Column 1 of A118884.
%H <a href="/index/Rec#order_08">Index entries for linear recurrences with constant coefficients</a>, signature (4,-4,0,-2,4,0,0,-1).
%F G.f. x^4 / ( (x-1)^2*(x^3+x^2+x-1)^2 ).
%F a(n) -2*a(n-1) + a(n-2) = A073778(n). - _R. J. Mathar_, Jul 26 2022
%e a(5)=4 because we have 00110,00111,00011 and 10011.
%p g:=z^4/(1-2*z+z^4)^2: gser:=series(g,z=0,40): seq(coeff(gser,z,n),n=0..36);
%Y Cf. A118884.
%K nonn
%O 0,6
%A _Emeric Deutsch_, May 03 2006
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