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%I #10 Jul 29 2024 05:31:33
%S 2,41,139,149,199,239,251,397,433,439,443,491,569,599,641,647,661,787,
%T 853,883,1031,1087,1097,1153,1187,1319,1423,1613,1619,1637,1657,1667,
%U 1697,1759,1789,2081,2129,2143,2221,2239,2459,2633,2689,2741,2753,2777
%N Primes p such that the p-th digit in the decimal expansion of Pi is 1.
%H Harvey P. Dale, <a href="/A088565/b088565.txt">Table of n, a(n) for n = 1..1000</a>
%e The 1st digit 1 in Pi is in the 2nd place of the digits 3,1,4,1,5,9,..., and 2 is prime, whence a(1) = 2. [Corrected and edited by _M. F. Hasler_, Jul 29 2024]
%t Select[Flatten[Position[RealDigits[Pi,10,2800][[1]],1]],PrimeQ] (* _Harvey P. Dale_, May 05 2019 *)
%o (PARI) pizeros(n,d) = { default(realprecision,5000); p = Pi; v = Vec(Str(p)); for(x=1,n, if(v[x] == Str(d) && isprime(x-1),print1(x-1",")) ) }
%o (PARI) A088565_upto(N=3456, d=1)={localprec(N+20); [p|p<-primes([1, #N=digits(Pi\10^-N)]), N[p]==d]} \\ _M. F. Hasler_, Jul 29 2024
%Y Primes in A014976.
%Y Cf. A088563, A088566 (the same for digits 0 and 2), A000796 (decimal digits of Pi).
%K nonn,base
%O 1,1
%A _Cino Hilliard_, Nov 19 2003