OFFSET
1,2
COMMENTS
See A192232 for definition of "k-sequence of reduction of [sequence] by [substitution]".
FORMULA
a(n) = 3*A122491(n+1).
G.f.: 3*x^2*(2-x)/(1-x)/(1-x-x^2)^2. [Colin Barker, Feb 11 2012]
MATHEMATICA
(See A192307.)
CROSSREFS
KEYWORD
nonn
AUTHOR
Clark Kimberling, Jun 27 2011
STATUS
approved