login
n + floor(4*sqrt(n+1)).
0

%I #6 Mar 30 2012 18:57:13

%S 6,8,11,12,14,16,18,20,21,23,24,26,27,29,31,32,33,35,36,38,39,41,42,

%T 44,45,46,48,49,50,52,53,54,56,57,59,60,61,62,64,65,66,68,69,70,72,73,

%U 74,76,77,78,79,81,82,83,84,86,87,88,89,91,92,93,95,96,97,98,99,101,102,103,104,106,107,108,109,111,112,113,114,116,117,118,119,120,122,123,124,125,126,128,129,130,131,132,134,135,136,137,139,140

%N n + floor(4*sqrt(n+1)).

%F a(n) = n + floor(4*sqrt(n+1))

%t a=16; b=16; Table[n+Floor[(a*n+b)^(1/2)],{n,100}]

%Y Cf. A184102.

%K nonn,easy

%O 1,1

%A _Clark Kimberling_, Jan 09 2011