%I A090770
%S A090770 2,48,23040,185794560,24257337753600,50821645356918374400,1704875112338069448032256000,
%T A090770 915241991059360703024740763172864000,7861748876453505095791592854589753555681280000,
%U A090770 1080506416218846625176535970968094253434513802154475520000,23760564710522006536076367353775273946279477197545\
               23173734842368000000
%N A090770 2^(n^2+2n+1)*Product_{j=1..n} (4^j-1).
%C A090770 The order of the p-Clifford group for an odd prime p is a*p^(n^2+2n+1)*Product_{j=1..n} 
               (p^(2*j)-1), where a = gcd(p+1,4). This is the sequence obtained 
               by (illegally) setting p = 2.
%H A090770 G. Nebe, E. M. Rains and N. J. A. Sloane, <a href="http://www.research.att.com/
               ~njas/doc/cliff2.html">Self-Dual Codes and Invariant Theory</a>, 
               Springer, Berlin, 2006.
%Y A090770 Cf. A001309, A003956.
%Y A090770 Cf. A092299 and A092301 (p=3), A092300 and A089989 (p=5), A090768 and 
               A090769 (p=7).
%Y A090770 A bisection of A003053, cf. A003923.
%Y A090770 Sequence in context: A002820 A053290 A056989 this_sequence A081960 A123742 
               A098694
%Y A090770 Adjacent sequences: A090767 A090768 A090769 this_sequence A090771 A090772 
               A090773
%K A090770 nonn
%O A090770 0,1
%A A090770 N. J. A. Sloane (njas(AT)research.att.com), Feb 10 2004