OFFSET
1,2
LINKS
A. Catanzaro, J. Feldman, M. Higgins, B. Kimball, H. Kirk, A. C Maravelias, and D. Sinha, LCM Optimal Paths, Girls' Angle Bulletin, Vol. 13, No. 4 (2020), 13-19.
EXAMPLE
For n = 3, the optimal path is 1, 2, 1, 3, which has cost 2 + 2 + 3 = 7.
For n = 4, the optimal path is 1, 3, 1, 2, 4, which has cost 3 + 3 + 2 + 4 = 12.
For n = 7, there are multiple optimal paths of which 1, 3, 6, 2, 4, 1, 5, 1, 7 is one and has cost 3 + 6 + 6 + 4 + 4 + 5 + 5 + 7 = 40.
For n = 20, an optimal path is 1, 11, 1, 13, 1, 17, 1, 19, 1, 7, 14, 2, 16, 8, 4, 12, 6, 18, 9, 3, 15, 5, 10, 20.
CROSSREFS
KEYWORD
nonn,hard,more
AUTHOR
Richard S. Chang, May 04 2020
EXTENSIONS
a(21)-a(28) from Bert Dobbelaere, Aug 22 2020
STATUS
approved