%I #19 Jun 29 2022 14:46:15
%S 0,0,0,0,1,2,3,4,6,8,10,12,14,16,19,22,25,28,32,36,40,44,48,52,57,62,
%T 67,72,78,84,90,96,102,108,115,122,129,136,144,152,160,168,176,184,
%U 193,202,211,220,230,240,250,260,270,280,291,302,313,324
%N a(n) = floor(n^2/10).
%H <a href="/index/Rec#order_12">Index entries for linear recurrences with constant coefficients</a>, signature (2,-1,0,0,0,0,0,0,0,1,-2,1).
%F G.f.: -x^4*(1+x^4) / ( (1+x)*(x^4-x^3+x^2-x+1)*(x^4+x^3+x^2+x+1)*(x-1)^3 ). - _R. J. Mathar_, Mar 08 2016
%p A056865 := proc(n)
%p floor(n^2/10) ;
%p end proc:
%p seq(A056865(n),n=0..100) ; # _R. J. Mathar_, Mar 08 2016
%t Floor[Range[0,60]^2/10] (* or *) LinearRecurrence[{2,-1,0,0,0,0,0,0,0,1,-2,1},{0,0,0,0,1,2,3,4,6,8,10,12},60] (* _Harvey P. Dale_, Jun 29 2022 *)
%o (PARI) a(n) = n^2\10; \\ _Michel Marcus_, Mar 08 2016
%Y Cf. A056864.
%Y Cf. A000290, A007590, A000212, A002620, A118015, A056827, A056834, A130519, A056838.
%K nonn,easy
%O 0,6
%A _N. J. A. Sloane_, Sep 02 2000