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, Table A.1 entry |E_O(S)|.
FORMULA
EXAMPLE
Triangle T(n,k) begins:
0;
0;
1, 2;
1, 3, 6;
2, 5, 6, 10, 16;
2, 6, 8, 14, 16, 26, 40;
3, 8, 11, 12, 18, 23, 27, 36, 42, 64, 96;
...
CROSSREFS
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