OFFSET
1,2
LINKS
Andrew Howroyd, Table of n, a(n) for n = 1..20
Eric Weisstein's World of Mathematics, Edge Cover
Eric Weisstein's World of Mathematics, King Graph
CROSSREFS
KEYWORD
nonn
AUTHOR
Eric W. Weisstein, Dec 24 2017
EXTENSIONS
Terms a(4) and beyond from Andrew Howroyd, Dec 26 2017
STATUS
approved