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Index of first occurrence of n-th prime in A001203, the continued fraction for Pi.
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%I #8 Mar 14 2015 13:52:08

%S 9,1,40,2,276,28,647,140,203,243,878,784,754,492,825,1547,907,868,

%T 1789,9215,898,6222,9131,4829,1516,6700,22640,872,11170,3204,223,

%U 10387,8299,30086,31079,12637,8486,20644,8451,53069,32093,16297,20276,1002,21264

%N Index of first occurrence of n-th prime in A001203, the continued fraction for Pi.

%C Until it is proved that every prime does indeed occur in A001203, we should tacitly understand a convention like "A107892(n) = 0 if A000040(n) does not occur in A001203". - _M. F. Hasler_, Mar 31 2008

%C Among first 1000000 terms of the continued fraction for Pi, the first absent primes have indices 129, 132, 137, 146, 147, 158, 160, 165, 170, 172, 175, 180, 182, 184, 189, 193, 197, 198, 199. The 200th prime is in the 947040th place, thus A107892(200)=947040.

%H M. F. Hasler (using data from H. Havermann), <a href="/A107892/b107892.txt">Table of n, a(n) for n=1,...,445</a>.

%F A107892(n) = A032523(A000040(n)) = min { k | A001203(k)=A000040(n) }. - _M. F. Hasler_, Mar 31 2008

%Y Cf. A032523: first occurrence of n in A001203.

%Y Cf. A138758, A138759.

%K nonn

%O 1,1

%A _Zak Seidov_, May 25 2005

%E Edited by _M. F. Hasler_, Mar 31 2008