OFFSET
2,2
COMMENTS
Triangular graphs are defined for n>=2.
LINKS
Alois P. Heinz, Table of n, a(n) for n = 2..20
Eric Weisstein's World of Mathematics, Spanning Tree
Eric Weisstein's World of Mathematics, Triangular Graph
CROSSREFS
KEYWORD
nonn
AUTHOR
Eric W. Weisstein, Jul 16 2011
STATUS
approved