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a(n) = n + [n*r/s] + [n*t/s]; r=1, s=-1+sqrt(2), t=1+sqrt(2).
3

%I #9 Sep 08 2022 08:45:56

%S 8,17,27,36,46,54,63,73,82,92,101,109,119,128,138,147,157,165,174,184,

%T 193,203,212,220,230,239,249,258,268,276,285,295,304,314,322,331,341,

%U 350,360,369,377,387,396,406,415,425,433,442,452,461,471,480,488,498,507,517,526,536,544,553,563,572,582,591,599,609,618,628,637,645,655,664,674,683,693,701,710,720,729,739,748,756,766

%N a(n) = n + [n*r/s] + [n*t/s]; r=1, s=-1+sqrt(2), t=1+sqrt(2).

%C (See A189380.)

%H G. C. Greubel, <a href="/A189381/b189381.txt">Table of n, a(n) for n = 1..10000</a>

%t r=1; s=-1+2^(1/2); t=1+2^(1/2);

%t f[n_] := n + Floor[n*s/r] + Floor[n*t/r];

%t g[n_] := n + Floor[n*r/s] + Floor[n*t/s];

%t h[n_] := n + Floor[n*r/t] + Floor[n*s/t];

%t Table[f[n], {n, 1, 120}] (* A189380 *)

%t Table[g[n], {n, 1, 120}] (* A189381 *)

%t Table[h[n], {n, 1, 120}] (* A189382 *)

%o (PARI) for(n=1, 100, print1(n + floor(n/(sqrt(2) -1)) + floor(n*(sqrt(2)+1)/(sqrt(2)-1)), ", ")) \\ _G. C. Greubel_, Apr 20 2018

%o (Magma) [n + Floor(n/(Sqrt(2) -1)) + Floor(n*(Sqrt(2)+1)/(Sqrt(2) - 1)): n in [1..100]]; // _G. C. Greubel_, Apr 20 2018

%Y Cf. A189380, A189382.

%K nonn

%O 1,1

%A _Clark Kimberling_, Apr 20 2011