OFFSET
1,2
COMMENTS
See A192232 for definition of "k-sequence of reduction of [sequence] by [substitution]".
FORMULA
a(n) = 2*A122491(n+1).
G.f.: 2*x*(2-x)/((1-x)*(1-x-x^2)^2). [Colin Barker, Feb 11 2012]
MATHEMATICA
(See A192305.)
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
Clark Kimberling, Jun 27 2011
STATUS
approved