2,2

a(n) = A008937(n-1)-1 = A018921(n-3)-1.

G.f.: x^2(x^2+x+1)/(x^4-2x+1).

Sequence in context: A117071 A019459 A152902 this_sequence A014172 A029879 A018084

Adjacent sequences: A027081 A027082 A027083 this_sequence A027085 A027086 A027087

nonn

Clark Kimberling (ck6(AT)evansville.edu)