%I #13 Sep 08 2022 08:45:56
%S 1,3,4,6,7,9,10,12,13,15,16,18,19,21,22,24,25,27,29,30,32,33,35,36,38,
%T 39,41,42,44,45,47,48,50,51,53,55,56,58,59,61,62,64,65,67,68,70,71,73,
%U 74,76,77,79,80,82,84,85,87,88,90,91,93,94,96,97,99,100,102,103,105,106,108,110,111,113,114,116,117,119,120,122,123,125,126,128,129,131
%N a(n) = A189933(n)/2.
%C (See A189933.)
%H G. C. Greubel, <a href="/A189935/b189935.txt">Table of n, a(n) for n = 1..10000</a>
%F Equals (n + floor(n*(sec(pi/5))^2) + floor(n*(tan(pi/5))^2))/2, for n>=1. - _G. C. Greubel_, Jan 13 2018
%t r=1; s=Sin[Pi/5]^2; t=Cos[Pi/5]^2;
%t a[n_] := n + Floor[n*s/r] + Floor[n*t/r];
%t b[*n_] := n + Floor[n*r/s] + Floor[n*t/s];
%t c[n_] := n + Floor[n*r/t] + Floor[n*s/t];
%t Table[a[n], {n, 1, 120}] (*A005408*)
%t Table[b[n], {n, 1, 120}] (*A189932*)
%t Table[c[n], {n, 1, 120}] (*A189933*)
%t Table[b[n]/2, {n, 1, 120}] (*A189934*)
%t Table[c[n]/2, {n, 1, 120}] (*A189935*)
%o (PARI) for(n=1,100, print1((n + floor(n/(cos(Pi/5))^2) + floor(n*(tan(Pi/5))^2))/2, ", ")) \\ _G. C. Greubel_, Jan 13 2018
%o (Magma) C<i> := ComplexField(); [(n + Floor(n/(Cos(Pi(C)/5))^2) + Floor(n*(Tan(Pi(C)/5))^2))/2: n in [1..100]]; // _G. C. Greubel_, Jan 13 2018
%Y Cf. A189932, A189933, A189934, A189926.
%K nonn
%O 1,2
%A _Clark Kimberling_, May 01 2011