%I A027639
%S A027639 4,32,3072,2752512,21139292160,1342091380654080,692647993190048071680,
%T A027639 2882479558988139892026900480,96342151992701835341576224427212800,
%U A027639 25811138467998276182105365247324712232550400
%N A027639 Order of unitary 2^n X 2^n group H_{n,4} acting on Siegel modular forms.
%D A027639 B. Runge, On Siegel modular forms I, J. Reine Angew. Math., 436 (1993), 
               57-85.
%D A027639 B. Runge, Codes and Siegel modular forms, Discrete Math. 148 (1996), 
               175-204.
%H A027639 <a href="Sindx_Gre.html#groups_modular">Index entries for sequences related 
               to modular groups</a>
%p A027639 2^(n^2+2*n+2)*product(2^'i'-1,'i'=1..n);
%Y A027639 Cf. A027639.
%Y A027639 Sequence in context: A081790 A053005 A012092 this_sequence A117620 A059904 
               A145645
%Y A027639 Adjacent sequences: A027636 A027637 A027638 this_sequence A027640 A027641 
               A027642
%K A027639 nonn,nice,easy
%O A027639 0,1
%A A027639 N. J. A. Sloane (njas(AT)research.att.com).