A076435 - OEIS

%I #21 Sep 11 2021 21:53:37

%S 1,2,2,4,3,6,2,6,5,8,2,10,3,6

%N Number of strongly regular simple graphs on n nodes.

%H Eric Weisstein's World of Mathematics, <a href="http://mathworld.wolfram.com/StronglyRegularGraph.html">Strongly Regular Graph</a>

%e 1: K_1 (1 graph)

%e 2: \bar K_2, P_2 = K_2 (2 graph)

%e 3: \bar K_3, C_3 = K_3 (2 graphs)

%e 4: \bar K_4, 2P_2, C_4, K_4 (4 graphs)

%e 5: C_5, \bar K_5, K_5 (3 graphs)

%e 6: 2C_3, K_6, \bar K_6, 3P_2, Ci_6(1,2), K_{3,3} (6 graphs)

%e Here, \bar denotes the graph complement and Ci_n(...) a circular graph.

%Y Cf. A005176, A076434, A088741.

%K nonn,nice,more

%O 1,2

%A _Eric W. Weisstein_, Oct 11 2002

%E a(10) from _Eric W. Weisstein_, Oct 30 2017

%E a(11)-a(14) from _Sean A. Irvine_, Sep 11 2021