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A189939 a(n) = n + [n*r/t] + [n*s/t];  r=1, s=sin(pi/8), t=cos(pi/8). 3
2, 4, 7, 9, 12, 14, 16, 19, 21, 24, 26, 28, 32, 34, 37, 39, 42, 44, 46, 49, 51, 54, 56, 58, 62, 64, 67, 69, 72, 74, 76, 79, 81, 84, 86, 88, 92, 94, 97, 99, 101, 104, 106, 109, 111, 114, 116, 118, 122, 124, 127, 129, 131, 134, 136, 139, 141, 144, 146, 148, 152, 154, 157, 159, 161, 164, 166, 169, 171, 173, 176, 178, 182, 184, 187, 189, 191 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

See A189937.

LINKS

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

FORMULA

A189937:  a(n) = n + [n*sin(pi/8)] + [n*cos(pi/8)].

A189938:  b(n) = n + [n*csc(pi/8)] + [n*cot(pi/8)].

A189939:  c(n) = n + [n*sec(pi/8)] + [n*tan(pi/8)].

MATHEMATICA

r=1; s=Sin[Pi/8]; t=Cos[Pi/8];

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}]  (*A189937*)

Table[b[n], {n, 1, 120}]  (*A189938*)

Table[c[n], {n, 1, 120}]  (*A189939*)

PROG

(PARI) for(n=1, 100, print1(n + floor(n/cos(Pi/8)) + floor(n*tan(Pi/8)), ", ")) \\ G. C. Greubel, Jan 13 2018

(MAGMA) C<i> := ComplexField(); [n + Floor(n/Cos(Pi(C)/8)) + Floor(n*Tan(Pi(C)/8)): n in [1..100]]; // G. C. Greubel, Jan 13 2018

CROSSREFS

Cf. A189937, A189938.

Sequence in context: A283964 A175884 A003151 * A219637 A189470 A189681

Adjacent sequences:  A189936 A189937 A189938 * A189940 A189941 A189942

KEYWORD

nonn

AUTHOR

Clark Kimberling, May 01 2011

STATUS

approved

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Last modified November 13 00:25 EST 2019. Contains 329083 sequences. (Running on oeis4.)