OFFSET
1,2
COMMENTS
LINKS
FORMULA
a(1) = 1. It appears that a(n) = 3*A038573(n-1), n >= 2.
EXAMPLE
Written as an irregular triangle in which the row lengths are the terms of A011782 the sequence begins:
1;
3;
3, 9;
3, 9, 9, 21;
3, 9, 9, 21, 9, 21, 21, 45;
3, 9, 9, 21, 9, 21, 21, 45, 9, 21, 21, 45, 21, 45, 45, 93;
...
Observation: at least the first 11 terms of the right border coincide with A068156.
CROSSREFS
KEYWORD
nonn,tabf
AUTHOR
David Applegate and Omar E. Pol, Jan 18 2016
STATUS
approved