OFFSET
1,1
COMMENTS
Apparently a(n) = A168281(n+1). - Georg Fischer, Nov 11 2021
EXAMPLE
27 terms: 2, 2 for beryllium, ... Every structure is palindromic (even and odd mixed). Also 2*A106314.
CROSSREFS
KEYWORD
nonn
AUTHOR
Paul Curtz, Apr 23 2008
STATUS
approved