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A238946
Maximal level size of arcs in divisor lattice D(n).
3
0, 1, 1, 1, 1, 2, 1, 1, 1, 2, 1, 3, 1, 2, 2, 1, 1, 3, 1, 3, 2, 2, 1, 3, 1, 2, 1, 3, 1, 6, 1, 1, 2, 2, 2, 4, 1, 2, 2, 3, 1, 6, 1, 3, 3, 2, 1, 3, 1, 3, 2, 3, 1, 3, 2, 3, 2, 2, 1, 7, 1, 2, 3, 1, 2, 6, 1, 3, 2, 6, 1, 5, 1, 2, 3, 3, 2, 6, 1, 3, 1, 2
OFFSET
1,6
COMMENTS
A divisor d of n has level given by bigomega(d) and in-degree given by omega(d). The number of arcs on a level is the sum of the in-degrees of all divisors on the level. - Andrew Howroyd, Mar 28 2020
LINKS
Andrew Howroyd, Table of n, a(n) for n = 1..1000 (terms 1..200 from Sung-Hyuk Cha)
S.-H. Cha, E. G. DuCasse, and L. V. Quintas, Graph Invariants Based on the Divides Relation and Ordered by Prime Signatures, arXiv:1405.5283 [math.NT], 2014.
PROG
(PARI) a(n)={if(n==1, 0, my(v=vector(bigomega(n))); fordiv(n, d, if(d>1, v[bigomega(d)] += omega(d))); vecmax(v))} \\ Andrew Howroyd, Mar 28 2020
CROSSREFS
Cf. A001221 (omega), A001222 (bigomega), A062799, A096825, A238955, A238968.
Sequence in context: A372772 A324191 A373957 * A379141 A351414 A349056
KEYWORD
nonn
AUTHOR
Sung-Hyuk Cha, Mar 07 2014
EXTENSIONS
a(1) corrected by Andrew Howroyd, Mar 28 2020
STATUS
approved