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URL: https://oeis.org/A238955

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A238955
Maximal level size of arcs in divisor lattice in graded colexicographic order.
3
0, 1, 1, 2, 1, 3, 6, 1, 3, 4, 7, 12, 1, 3, 5, 8, 11, 18, 30, 1, 3, 5, 6, 8, 12, 15, 19, 24, 38, 60, 1, 3, 5, 7, 8, 13, 16, 19, 20, 30, 37, 46, 58, 90, 140, 1, 3, 5, 7, 8, 8, 13, 17, 20, 23, 20, 31, 36, 43, 52, 47, 66, 80, 100, 122, 185, 280
OFFSET
0,4
LINKS
Andrew Howroyd, Table of n, a(n) for n = 0..2713 (rows 0..20)
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.
FORMULA
T(n,k) = A238946(A036035(n,k)).
EXAMPLE
Triangle T(n,k) begins:
0;
1;
1, 2;
1, 3, ;
1, 3, 4, 7, 12;
1, 3, 5, 8, 11, 18, 30;
1, 3, 5, 6, 8, 12, 15, 19, 24, 38, 60;
...
PROG
(PARI) \\ here b(n) is A238946.
b(n)={if(n==1, 0, my(v=vector(bigomega(n))); fordiv(n, d, if(d>1, v[bigomega(d)] += omega(d))); vecmax(v))}
N(sig)={prod(k=1, #sig, prime(k)^sig[k])}
Row(n)={apply(s->b(N(s)), [Vecrev(p) | p<-partitions(n)])}
{ for(n=0, 6, print(Row(n))) } \\ Andrew Howroyd, Apr 25 2020
CROSSREFS
Cf. A238946 in graded colexicographic order.
Sequence in context: A077877 A144867 A081520 * A238968 A217891 A322044
KEYWORD
nonn,tabf
AUTHOR
Sung-Hyuk Cha, Mar 07 2014
EXTENSIONS
Offset changed and terms a(50) and beyond from Andrew Howroyd, Apr 25 2020
STATUS
approved