A189935 a(n) = A189933(n)/2.

1, 3, 4, 6, 7, 9, 10, 12, 13, 15, 16, 18, 19, 21, 22, 24, 25, 27, 29, 30, 32, 33, 35, 36, 38, 39, 41, 42, 44, 45, 47, 48, 50, 51, 53, 55, 56, 58, 59, 61, 62, 64, 65, 67, 68, 70, 71, 73, 74, 76, 77, 79, 80, 82, 84, 85, 87, 88, 90, 91, 93, 94, 96, 97, 99, 100, 102, 103, 105, 106, 108, 110, 111, 113, 114, 116, 117, 119, 120, 122, 123, 125, 126, 128, 129, 131

Offset

1,2

Comments

(See A189933.)

Links

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

Formula

Equals (n + floor(n*(sec(pi/5))^2) + floor(n*(tan(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/(cos(Pi/5))^2) + floor(n*(tan(Pi/5))^2))/2, ", ")) \\ G. C. Greubel, Jan 13 2018
(Magma) C<i> := ComplexField(); [(n + Floor(n/(Cos(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, A189934, A189926.

Sequence in context: A049624 A084056 A032766 * A329987 A329962 A258574

Adjacent sequences: A189932 A189933 A189934 * A189936 A189937 A189938

Keyword

nonn

Author

Clark Kimberling, May 01 2011

Status

approved