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%I #11 Feb 25 2023 09:37:16
%S 1,1,4,1054163
%N Number of nonisomorphic Steiner quadruple systems (SQS's) S(3,4,v) on v = 6n+2 or 6n+4 points.
%C A051390 is the official version of this sequence and has all the references etc.
%H Eric Weisstein's World of Mathematics, <a href="http://mathworld.wolfram.com/SteinerQuadrupleSystem.html">Steiner Quadruple System</a>
%H <a href="/index/St#Steiner">Index entries for sequences related to Steiner systems</a>
%e There are 4 nonisomorphic SQS's on 14 points.
%Y Cf. A124120, A030129, A001201, A030128, A051390.
%K nonn,hard,more
%O 1,3
%A _N. J. A. Sloane_, Nov 30 2006