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 A065570 Numbers k such that the first k ternary digits found in the decimal expansion of Pi form a prime. 0
 264, 274, 322, 751, 3112, 24842, 32731 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 LINKS MATHEMATICA p = First[ RealDigits[ Pi, 10, 10^5]]; p = p[[ Select[ Range[10^5], p[[ # ]] == 0 || p[[ # ]] == 1 || p[[ # ]] == 2 & ]]]; Do[ If[ PrimeQ[ FromDigits[ Take[p, n], 3]], Print[n]], {n, 1, 4000} ] Module[{nn=30000, pd}, pd=Select[RealDigits[Pi, 10, nn][[1]], #<3&]; Select[ Range[ Length[pd]], PrimeQ[FromDigits[Take[pd, #], 3]]&]] (* The program generates the first five terms of the sequence. To generate more, increase the constant for "nn, " but it will take a long time to run and the value of nn may be to be 150, 000 or more. *) (* Harvey P. Dale, Jul 31 2020 *) CROSSREFS Cf. A065832. Sequence in context: A229480 A266036 A157828 * A345586 A345844 A253694 Adjacent sequences:  A065567 A065568 A065569 * A065571 A065572 A065573 KEYWORD nonn,base AUTHOR Robert G. Wilson v, Nov 30 2001 EXTENSIONS a(6)-a(7) from Chai Wah Wu, Apr 07 2020 STATUS approved

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Last modified July 4 20:49 EDT 2022. Contains 355086 sequences. (Running on oeis4.)