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A225802 Position of first occurrence of n in continued fraction for Pi, or -1 if n never occurs. 2

%I

%S 3,8,0,29,39,31,1,43,129,99,275,54,27,12,2,77,646,136,139,179,213,82,

%T 202,90,790,111,573,174,242,146,877,454,530,420,1007,593,783,3040,720,

%U 1871,753,118,491,428,80,3199,824,282,3026,464,1436,3383,1546,1863,445,1017

%N Position of first occurrence of n in continued fraction for Pi, or -1 if n never occurs.

%C Correctly indexed version of A032523.

%C All positive integers <= 49003 occur in the first 15000000000 terms of the c.f. (the first that do not are 49004, 50471, 53486, 56315, 58255, ...) - _Eric W. Weisstein_, Jul 27 2013

%H Eric W. Weisstein, <a href="/A225802/b225802.txt">Table of n, a(n) for n = 1..49003</a>

%H Eric Weisstein's World of Mathematics, <a href="http://mathworld.wolfram.com/PiContinuedFraction.html">Pi Continued Fraction</a>

%F a(n) = A032523(n) - 1.

%e The continued fraction of Pi is [a_0; a_1, a_2, ...] = [3; 7, 15, 1, 292, 1, 1, 1, 2, 1, ...], so

%e a(1) = 3 (1 first occurs at term a_3);

%e a(2) = 8 (2 first occurs at term a_8);

%e a(3) = 0 (3 first occurs at term a_0).

%Y Cf. A032523 (= a(n) + 1).

%Y Cf. A001203 (continued fraction of Pi).

%K nonn

%O 1,1

%A _Eric W. Weisstein_, Jul 27 2013

%E "Escape clause" added to definition by _Jianing Song_, Apr 06 2019

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Last modified September 26 20:36 EDT 2020. Contains 337374 sequences. (Running on oeis4.)