%I #11 Mar 19 2024 10:25:12
%S 0,0,0,0,0,0,0,0,0,1,1,2,2,3,4,5,6,8,8,11,12,14,16,19,20,24,26,29,32,
%T 37,38,44,47,51,56,62,64,72,76,82,88,96,99,109,115,122,130,140,144,
%U 157,164,173,183,195,201,216,225,236,248,263,270,288,299,312,327,344,353,374
%N Dimension of the space of Siegel cusp forms of genus 2 and weight 2k which are not SaitoKurokawa lifts of forms of genus 1.
%C Also the dimension of the largest Heckeclosed subspace of forms in S_k(Gamma_2) which satisfy the RamanujanPetersson conjecture. These forms are also characterized by the property that their (Andrianov) spinor zeta function does not have any pole.
%D M. Eichler and D. Zagier, The Theory of Jacobi Forms, Birkhaeusser, 1985.
%D T. Oda, On the poles of Andrianov Lfunctions, Math. Ann. 256(3), p. 323340, 1981.
%D R. Weissauer, The Ramanujan conjecture for genus two Siegel modular forms (an application of the trace formula). Preprint, Mannheim (1993)
%H <a href="/index/Rec#order_16">Index entries for linear recurrences with constant coefficients</a>, signature (0,1,1,0,0,1,1,2,1,1,0,0,1,1,0,1).
%F For k > 1 we have a(k) = A165684(k)  A008615(2k5).
%F Conjectured G.f.: x^10*(x^7+x^6x^2x1) / ((1x^2)*(1x^3)*(1x^5)*(1x^6)).  _Colin Barker_, Mar 30 2013
%e a(20)=1 because there is exactly one Siegel modular form of genus 2 and weight 20 which is not a lift of some form of genus 1.
%Y Cf. A165684 for the full space of Siegel cusp forms. See also A029143, A027640, A165685.
%K nonn,easy
%O 1,12
%A Kilian Kilger (kilian(AT)nihilnovi.de), Sep 26 2009
