login
The OEIS is supported by the many generous donors to the OEIS Foundation.

 

Logo
Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A016274 Numbers k where the fractional part of tan(k) decreases monotonically to 0. 1

%I #18 Mar 16 2021 01:25:15

%S 1,4,11,22,80,355,11270,26087,286602,301419,5419351,21390802,

%T 144316263,167004362,2549491779,2816733503,5900708730,8984683957,

%U 30038027098,31037086001,84380376926,199507230388,302095980547,306607554715

%N Numbers k where the fractional part of tan(k) decreases monotonically to 0.

%e From _Jon E. Schoenfield_, Mar 16 2021: (Start)

%e "Fractional part" of x here is defined as x - floor(x), so, e.g., since tan(11) = -225.95084..., its fractional part is -225.95084... - (-226) = 0.04915...

%e Terms and fractional parts are as follows:

%e .

%e n k = a(n) tan(k) - floor(tan(k))

%e -- ------------ ----------------------

%e 1 1 0.55740772465490223...

%e 2 4 0.15782128234957758...

%e 3 11 0.04915354580485797...

%e 4 22 0.00885165604168446...

%e 5 80 0.00365494560707973...

%e 6 355 0.00003014435337318...

%e 7 11270 0.00001427816936167...

%e 8 26087 0.00000550749362596...

%e 9 286602 0.00000029389002962...

%e 10 301419 0.00000022540911069...

%e 11 5419351 0.00000003820047507...

%e 12 21390802 0.00000001171381405...

%e 13 144316263 0.00000000559574875...

%e 14 167004362 0.00000000046598564...

%e 15 2549491779 0.00000000044744949...

%e 16 2816733503 0.00000000037258234...

%e 17 5900708730 0.00000000022284805...

%e 18 8984683957 0.00000000007311376...

%e 19 30038027098 0.00000000006960700...

%e 20 31037086001 0.00000000001573866...

%e 21 84380376926 0.00000000001010671...

%e 22 199507230388 0.00000000000293624...

%e 23 302095980547 0.00000000000151187...

%e 24 306607554715 0.00000000000103988...

%e (End)

%o (PARI) lista(nn) = {my(m = oo, nm); for (n=1, nn, if ((nm=frac(tan(n))) < m, print1(n, ", "); m = nm););} \\ _Michel Marcus_, Jan 17 2019

%Y Cf. A019435 (increases).

%K nonn

%O 1,2

%A _Michel ten Voorde_

%E Offset changed to 1 and more terms from _Sean A. Irvine_, Jan 16 2019

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recents
The OEIS Community | Maintained by The OEIS Foundation Inc.

License Agreements, Terms of Use, Privacy Policy. .

Last modified April 24 14:32 EDT 2024. Contains 371960 sequences. (Running on oeis4.)