OFFSET
1,3
COMMENTS
a(n) is also the largest possible radio number for a graph on n nodes.
LINKS
D. D.-F. Liu and X. Zhu, Multilevel Distance Labelings for Paths and Cycles, SIAM J. Disc. Math. 19, 610-621, 2005.
Eric Weisstein's World of Mathematics, Path Graph
Eric Weisstein's World of Mathematics, Radio Number
FORMULA
a(n) = A236283(n-1) for n > 1, n != 3.
a(n) = 0 for n = 1,
= 3 for n = 3,
= (n - 2)*n/2 + 1 for n even,
= (n - 3)*(n + 1)/2 + 4 for n odd.
G.f.: x^2*(1 + x^2)*(1 + x - 2*x^2 + x^3)/((1 - x)^3*(1 + x)).
CROSSREFS
KEYWORD
nonn
AUTHOR
Eric W. Weisstein, Jan 10 2021
STATUS
approved