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Let G be an n-node graph with valencies d_1 .. d_n say; let m = (d_1 + ... + d_n)/n and s = n*Sum( (d_i-m)^2 ) be the scaled degree variance; a(n) gives number of different values taken by s.
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%I #22 Jan 13 2021 10:33:12

%S 1,1,2,4,11,14,43,34,102,111,296,262

%N Let G be an n-node graph with valencies d_1 .. d_n say; let m = (d_1 + ... + d_n)/n and s = n*Sum( (d_i-m)^2 ) be the scaled degree variance; a(n) gives number of different values taken by s.

%C Computed by Jan Hagberg, Dept. Statistics, Stockholm Univ., Sweden.

%H J. Hagberg, <a href="http://gauss.stat.su.se/rr/RR2000_8.pdf">Centrality testing and the distribution of the degree variance in Bernoulli graphs</a>, Research Report 2000:8, Department of Statistics, Stockholm University, 2000.

%H Sean A. Irvine, <a href="https://github.com/archmageirvine/joeis/blob/master/src/irvine/oeis/a038/A038193.java">Java program</a> (github)

%K nonn,nice,more

%O 1,3

%A _N. J. A. Sloane_

%E Hagberg reference from C. Ronaldo (aga_new_ac(AT)hotmail.com), Dec 29 2004

%E a(10) corrected and a(11) added by _Sean A. Irvine_, Jan 10 2021

%E a(12) from _Sean A. Irvine_, Jan 13 2021