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A189934 a(n) = A189932(n)/2. 3
2, 5, 8, 11, 14, 17, 20, 23, 26, 28, 31, 34, 37, 40, 43, 46, 49, 52, 54, 57, 60, 63, 66, 69, 72, 75, 78, 81, 83, 86, 89, 92, 95, 98, 101, 104, 107, 109, 112, 115, 118, 121, 124, 127, 130, 133, 136, 138, 141, 144, 147, 150, 153, 156, 159, 162, 164, 167, 170, 173, 176, 179, 182, 185, 188, 191, 193, 196, 199, 202, 205, 208, 211, 214, 217 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

See A189932.

LINKS

G. C. Greubel, Table of n, a(n) for n = 1..10000

FORMULA

Equals (n + floor(n*(csc(pi/5))^2) + floor(n*(cot(pi/5))^2))/2, for n>=1. - G. C. Greubel, Jan 13 2018

MATHEMATICA

r=1; s=Sin[Pi/5]^2; t=Cos[Pi/5]^2;

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}]  (*A005408*)

Table[b[n], {n, 1, 120}]  (*A189932*)

Table[c[n], {n, 1, 120}]  (*A189933*)

Table[b[n]/2, {n, 1, 120}]  (*A189934*)

Table[c[n]/2, {n, 1, 120}]  (*A189935*)

PROG

(PARI) for(n=1, 100, print1((n + floor(n/(sin(Pi/5))^2) + floor(n/(tan(Pi/5))^2))/2, ", ")) \\ G. C. Greubel, Jan 13 2018

(MAGMA) C<i> := ComplexField(); [(n + Floor(n/(Sin(Pi(C)/5))^2) + Floor(n/(Tan(Pi(C)/5))^2))/2: n in [1..100]]; // G. C. Greubel, Jan 13 2018

CROSSREFS

Cf. A189932, A189933, A189935.

Sequence in context: A329961 A078608 A329988 * A189386 A292661 A016789

Adjacent sequences:  A189931 A189932 A189933 * A189935 A189936 A189937

KEYWORD

nonn

AUTHOR

Clark Kimberling, May 01 2011

STATUS

approved

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Last modified May 31 13:01 EDT 2020. Contains 334748 sequences. (Running on oeis4.)