OFFSET
1,2
LINKS
Carole Dubois, Table of n, a(n) for n = 1..5001
EXAMPLE
The sequence starts hereunder with the S line (this sequence); then comes the Q line (cumulative sum of S' terms); then comes the R line (digital root of Q at this point):
S = 1, 9, 10, 8, 12, 6, 16, 2, 18, 27, 28, 14, 3, 36, 40,...
Q = 1, 10, 20, 28, 40, 46, 62, 64, 82, 109, 137, 151, 154, 190, 230,...
R = 1, 1, 2, 1, 4, 1, 8, 1, 1, 1, 2, 7, 1, 1, 5,...
We see that the term R divides the term S on top of the 3-level column.
CROSSREFS
KEYWORD
base,nonn
AUTHOR
Eric Angelini and Carole Dubois, May 08 2020
STATUS
approved