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A355572
Largest LCM of partitions of n into odd parts.
1
1, 1, 3, 3, 5, 5, 7, 15, 15, 21, 21, 35, 35, 45, 105, 105, 105, 105, 165, 165, 315, 315, 385, 385, 495, 1155, 1155, 1365, 1365, 1365, 1365, 3465, 3465, 4095, 4095, 5005, 5005, 6435, 15015, 15015, 15015, 15015, 19635, 19635, 45045, 45045, 45045, 45045, 58905, 58905, 69615, 69615
OFFSET
1,3
COMMENTS
The largest LCM is attained for a partition of n into powers of distinct odd primes and 1's.
LINKS
Petr Gregor, Arturo Merino, and Torsten Mütze, The Hamilton compression of highly symmetric graphs, arXiv preprint arXiv:2205.08126 [math.CO], 2022.
EXAMPLE
The partitions of n=8 into odd parts are 7+1, 5+3, 5+1+1+1, 3+3+1+1, 3+1+1+1+1+1, 1+1+1+1+1+1+1+1, and the partition with largest LCM among those is 5+3, which has LCM(5,3)=5*3=15, so a(8)=15.
PROG
(PARI) a(n) = my(x=1); forpart(p=n, if (!#select(x->((x%2)==0), Vec(p)), x = max(x, lcm(Vec(p))))); x; \\ Michel Marcus, Jul 08 2022
CROSSREFS
KEYWORD
nonn
AUTHOR
Torsten Muetze, Jul 07 2022
STATUS
approved