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a(n) = n + [rn/s] + [tn/s] + [un/s], where []=floor and r=sin(Pi/2), s=sin(Pi/3), t=sin(Pi/4), u=sin(Pi/5).
4

%I #9 Apr 11 2021 01:31:06

%S 2,6,10,13,17,20,24,28,32,35,38,42,46,50,54,57,60,64,67,72,76,78,82,

%T 86,89,94,98,101,104,108,112,115,119,123,126,130,134,137,141,145,148,

%U 152,156,158,162,167,170,174,178,180,184,189,192,196,199,203,206,210,215,217,221,225,228,232,237,239,243,247,250,254,257,261,265,269,272,276,279,283,287,291,294,297,301,305,309,313,317,319,323,327,331,335,338,341,345,349,353,357,360,363,367,371,374,378,382,385,389,393,395,400,404,408,411,415,418,421,426,430,433,436

%N a(n) = n + [rn/s] + [tn/s] + [un/s], where []=floor and r=sin(Pi/2), s=sin(Pi/3), t=sin(Pi/4), u=sin(Pi/5).

%C The sequences A184924-A184928 partition the positive integers:

%C A184928: 1, 5, 6, 11, 14, 18, 21, 23, 27, ...

%C A184929: 2, 6, 10, 13, 17, 20, 24, 28, 32, ...

%C A184930: 3, 7, 12, 16, 22, 25, 29, 34, 39, ...

%C A184931: 4, 9, 15, 19, 26, 31, 36, 41, 47, ...

%C Jointly rank the sets {h*r}, {i*s}, {j*t}, {k*u}, where h>=1, i>=1, j>=1, k>=1. The position of n*s in the joint ranking is n + [rn/s] + [tn/s] + [un/s], and likewise for the positions of n*r, n*t, and n*u.

%t r=Sin[Pi/2]; s=Sin[Pi/3]; t=Sin[Pi/4]; u=Sin[Pi/5];

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

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

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

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

%t Table[a[n],{n,1,120}] (* A184928 *)

%t Table[b[n],{n,1,120}] (* A184929 *)

%t Table[c[n],{n,1,120}] (* A184930 *)

%t Table[d[n],{n,1,120}] (* A184931 *)

%Y Cf. A184928, A184930, A184931.

%K nonn

%O 1,1

%A _Clark Kimberling_, Jan 26 2011