%I #4 Feb 01 2018 21:00:55
%S 1,3,6,10,21,36,55,78,105,136,171,210,253,300,351
%N Intersection of A264041 and A000217.
%F Conjectures (Start)
%F G.f.: x*(1 + 6*x^4 - 3*x^5) / (1 - x)^3.
%F a(n) = 6 - 7*n + 2*n^2 for n>3.
%F a(n) = 3*a(n-1) - 3*a(n-2) + a(n-3) for n>3.
%F (End)
%Y Cf. A000217, A264041.
%K nonn,more
%O 1,2
%A _Colin Barker_, Jan 31 2018