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%I #7 Mar 30 2012 18:39:12
%S 1,3,5,11,344,1054,1764,2474,3184,3894,4604,5314,6024,6734,7444,8154,
%T 8864,9574,10284,10994,11704,12414,13124,13834,14544,15254,15964,
%U 16674,17384,18094,18804,19514,20224,20934,21644,22354,23064,23774,24484
%N a(0)=1; a(n) is the smallest integer > a(n-1) such that sin(a(n)) is closer to an integer (here 0 or -1) than sin(a(n-1)).
%e sin(1)=0.84147..., sin(2)=0.90929..., sin(3)=0.14112..., hence a(2)=3
%o (PARI) x=1; y=1; a(n)=if(n<0,0,b=y+1; while(frac(sin(b))>frac(sin(x)),b++); x=b; y=b; b)
%Y Cf. A046947 ( for abs(sin(x)) ).
%K nonn
%O 0,2
%A _Benoit Cloitre_, Feb 01 2003