OFFSET
1,5
COMMENTS
This is an irregular table related to labeled rooted trees and to Bell numbers.
A181511 contains the same values, without repetition.
EXAMPLE
1;
1,1;
1,2,2;
1,3,3,6,6;
1,4,4,12,12,24,24;
1,5,5,5,20,20,20,60,60,120,120;
1,6,6,6,30,30,30,30,120,120,120,360,360,720,720;
CROSSREFS
KEYWORD
nonn,tabf
AUTHOR
Alford Arnold, Oct 26 2010
STATUS
approved