A274101 - OEIS

%I #14 Jun 20 2016 19:39:16

%S 0,0,0,0,1,1,-1,-1,2,0,-2,0,3,0,-3,0,4,-2,-4,2,4,-3,-4,3,4,-5,-4,5,3,

%T -6,-3,6,2,-8,-2,8,1,-9,-1,9,0,-10,0,10,-2,-11,2,11,-4,-11,4,11,-6,

%U -12,6,12,-8,-12,8,12,-10,-11,10,11,-12,-10,12,10,-14,-9,14,9,-16,-8,16,8,-18,-7,18,7,-19,-5

%N a(n) = nearest integer to k*sin(sqrt(k)+j*Pi/2) where n = 4*k+j, 0<=j<4.

%H N. J. A. Sloane, <a href="/A274101/b274101.txt">Table of n, a(n) for n = 0..10000</a>

%p Digits:=50:

%p ft:=proc(n,t) local k,j;

%p j:=(n mod t); k:=(n-j)/t;

%p round(evalf(k*sin(sqrt(k)+j*Pi/2)));

%p end;

%p [seq(ft(n,4),n=0..120)];

%Y Sequences of the same type: A272695, A274086, A274087, A274088, A274090, A274091, A274092, A274095, A274096, A274097, A274101, A274102.

%K sign

%O 0,9

%A _N. J. A. Sloane_, Jun 11 2016

%E Definition corrected by _N. J. A. Sloane_, Jun 20 2016