A187323 - OEIS

%I #17 Jul 24 2023 08:04:00

%S 0,0,1,2,4,4,6,6,8,9,10,10,13,13,14,15,17,17,19,19,21,22,23,23,26,26,

%T 27,28,30,30,32,32,34,35,36,36,39,39,40,41,43,43,45,45,47,48,49,49,52,

%U 52,53,54,56,56,58,58,60,61,62,62,65,65,66,67,69,69,71,71,73,74,75,75,78,78,79,80,82,82,84,84,86,87,88,88,91,91,92,93,95,95,97,97,99,100,101,101,104,104,105,106,108,108,110,110,112,113,114,114,117,117,118,119,121,121,123,123,125,126,127,127,130

%N a(n) = floor(n/2) + floor(n/3) + floor(n/4).

%H <a href="/index/Rec#order_07">Index entries for linear recurrences with constant coefficients</a>, signature (0,0,1,1,0,0,-1).

%F a(n) = floor(n/2) + floor(n/3) + floor(n/4).

%F From _Robert Israel_, Jul 23 2023: (Start)

%F a(n+12) = a(n) + 13.

%F G.f.: (3*x^6 + 3*x^5 + 4*x^4 + 2*x^3 + x^2)/(x^7 - x^4 - x^3 + 1). (End)

%t Table[Total[Floor[n/{2,3,4}]],{n,0,120}] (* _Harvey P. Dale_, Jun 14 2014 *)

%o (Python)

%o def A187323(n): return 3*(n>>2)+bool(n&2)+n//3 # _Chai Wah Wu_, Jan 31 2023

%K nonn,easy

%O 0,4

%A _Clark Kimberling_, Mar 08 2011