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A238968 Maximal level size of arcs in divisor lattice in canonical order. 3
0, 1, 1, 2, 1, 3, 6, 1, 3, 4, 7, 12, 1, 3, 5, 8, 11, 18, 30, 1, 3, 5, 8, 6, 12, 19, 15, 24, 38, 60, 1, 3, 5, 8, 7, 13, 20, 16, 19, 30, 46, 37, 58, 90, 140, 1, 3, 5, 8, 7, 13, 20, 8, 17, 20, 31, 47, 23, 36, 43, 66, 100, 52, 80, 122, 185, 280 (list; graph; refs; listen; history; text; internal format)
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(A063008(n,k)). - Andrew Howroyd, Mar 28 2020

EXAMPLE

Triangle T(n,k) begins:

  0;

  1;

  1, 2;

  1, 3, 6;

  1, 3, 4, 7, 12;

  1, 3, 5, 8, 11, 18, 30;

  1, 3, 5, 8,  6, 12, 19, 15, 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)), vecsort([Vecrev(p) | p<-partitions(n)], , 4))}

{ for(n=0, 8, print(Row(n))) } \\ Andrew Howroyd, Mar 28 2020

CROSSREFS

Cf. A238955 in canonical order.

Cf. A063008, A238946.

Sequence in context: A144867 A081520 A238955 * A217891 A322044 A010251

Adjacent sequences:  A238965 A238966 A238967 * A238969 A238970 A238971

KEYWORD

nonn,tabf

AUTHOR

Sung-Hyuk Cha, Mar 07 2014

EXTENSIONS

Offset changed and terms a(50) and beyond from Andrew Howroyd, Mar 28 2020

STATUS

approved

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Last modified July 28 00:54 EDT 2021. Contains 346316 sequences. (Running on oeis4.)