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A189928
c(n) = n + [n*r/t] + [n*s/t]; r=1, s=sin(Pi/5), t=cos(Pi/5), where [] denotes the floor function.
3
2, 5, 8, 10, 14, 17, 20, 22, 26, 29, 31, 34, 38, 41, 43, 46, 50, 53, 55, 58, 61, 64, 67, 70, 73, 76, 79, 82, 85, 88, 91, 94, 96, 100, 103, 106, 108, 111, 115, 118, 120, 123, 127, 129, 132, 135, 139, 141, 144, 147, 151, 153, 156, 159, 161, 165, 168, 171, 173, 177, 180
OFFSET
1,1
COMMENTS
See A189926.
LINKS
FORMULA
A189926: a(n) = n + [n*sin(Pi/5)] + [n*cos(Pi/5)].
A189927: b(n) = n + [n*csc(Pi/5)] + [n*cot(Pi/5)].
A189928: c(n) = n + [n*sec(Pi/5)] + [n*tan(Pi/5)].
MATHEMATICA
r=1; s=Sin[Pi/5]; t=Cos[Pi/5];
a[n_] := n + Floor[n*s/r] + Floor[n*t/r];
b[n_] := n + Floor[n*r/s] + Floor[n*t/s];
c[n_] := n + Floor[n*r/t] + Floor[n*s/t];
Table[a[n], {n, 1, 120}] (* A189926 *)
Table[b[n], {n, 1, 120}] (* A189927 *)
Table[c[n], {n, 1, 120}] (* A189928 *)
PROG
(PARI) for(n=1, 100, print1(n + floor(n/cos(Pi/5)) + floor(n*tan(Pi/5)), ", ")) \\ G. C. Greubel, Jan 13 2018
(Magma) C<i> := ComplexField(); [n + Floor(n/Cos(Pi(C)/5)) + Floor(n*Tan(Pi(C)/5)): n in [1..100]]; // G. C. Greubel, Jan 13 2018
CROSSREFS
Sequence in context: A263831 A189457 A189362 * A309518 A169922 A157481
KEYWORD
nonn
AUTHOR
Clark Kimberling, May 01 2011
STATUS
approved