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A248945 Decimal expansion of Sum_{n >= 1} (sin(1/n))^2. 7

%I #17 Jan 15 2024 19:36:38

%S 1,3,2,6,3,2,4,4,0,5,2,6,6,6,5,3,4,3,3,5,4,9,4,0,3,7,7,8,1,4,2,6,8,8,

%T 9,9,6,8,3,1,1,3,3,7,1,0,8,2,5,7,1,8,8,9,5,5,5,5,6,6,4,1,4,2,4,4,0,3,

%U 9,8,9,8,3,4,3,1,7,0,8,2,5,3,4,9,1,5,4,8,3,8,3,1,0,6,8,4,4,8,5,9,6,3,8,3,5

%N Decimal expansion of Sum_{n >= 1} (sin(1/n))^2.

%H Vaclav Kotesovec, <a href="/A248945/b248945.txt">Table of n, a(n) for n = 1..500</a>

%H Steve Chow, <a href="https://www.youtube.com/watch?v=TkKlr9P2ks4">You did this wrong #Calc2Final</a>, blackpenredpen video (2018)

%e 1.32632440526665343354940377814268899683113371082571889555566414244...

%p evalf(sum((sin(1/n))^2, n=1..infinity), 120); # _Vaclav Kotesovec_, Oct 20 2014

%t (* N[Sum[Sin[1/n]^2, {n, 1, Infinity}], 120], yields only 26 correct decimals, N[Sum[Sin[1/n]^2, {n, 1, 10000}], 120], yields only 7 correct decimals! *)

%o (PARI) default(realprecision,150); sumpos(n=1,(sin(1/n))^2) \\ _Vaclav Kotesovec_, Oct 20 2014

%Y Cf. A248946, A248947, A248949.

%K nonn,easy,cons

%O 1,2

%A _Clark Kimberling_, Oct 18 2014

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Last modified April 23 05:37 EDT 2024. Contains 371906 sequences. (Running on oeis4.)