%I #8 Mar 30 2012 18:40:44

%S 2,5,17,53,167,515,1577,4793,14507,43775,131837,396533,1191647,

%T 3579035,10745297,32252273,96789587,290434295,871433957,2614564013,

%U 7844216327,23533697555,70603189817,211813763753,635449679867,1906365816815

%N Number of primitive H-invariant prime ideals in O_q(M_{2,n}) generic quantum matrices.

%C Equation given in Bell, Launois, Nguyen, page 2.

%H J. Bell, S. Launois and N. Nguyen, <a href="http://arXiv.org/abs/0705.3413">Dimension and enumeration of primitive ideals in quantum algebras</a>, arXiv:0705.3413 v2, Nov 29, 2007.

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

%F G.f.: x(2-5x+2x^2+3x^3)/((1-x)(1-3x)(1-2x)(1+x)). [From _R. J. Mathar_, Oct 30 2008]

%e a(8) = ((3^(8 + 1)) - (2^(8 + 1)) + ((-1)^(8 + 1)) + 2) / 4 = 4793.

%K easy,nonn

%O 1,1

%A _Jonathan Vos Post_, Nov 30 2007

%E Corrected the definition: Changed O_q(M_n) to O_q(M_{2,n}) Karel Casteels (kcasteel(AT)sfu.ca), Feb 20 2010