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A373895
a(n) = ceiling((2^n+n-1)/n).
1
2, 3, 4, 5, 8, 12, 20, 33, 58, 104, 188, 343, 632, 1172, 2186, 4097, 7712, 14565, 27596, 52430, 99866, 190652, 364724, 699052, 1342179, 2581112, 4971028, 9586982, 18512792, 35791396, 69273668, 134217729, 260301050, 505290272, 981706812, 1908874355, 3714566312, 7233629132, 14096302922, 27487790696
OFFSET
1,1
COMMENTS
a(n) is the irregularity strength of the hypercube graph Q_n for n >= 2.
LINKS
G. Ebert, J. Hammenter, F. Lazebnik, and A. Woldar, Irregularity Strengths for Certain Graphs, Congressus Numerantium 71 (1990), 39-52.
Eric Weisstein's World of Mathematics, Hypercube Graph.
Eric Weisstein's World of Mathematics, Irregularity Strength.
MATHEMATICA
Array[Ceiling[(2^# + # - 1)/#] &, 120] (* Michael De Vlieger, Jun 21 2024 *)
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
Eric W. Weisstein, Jun 21 2024
STATUS
approved