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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
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 March 28 17:25 EDT 2024. Contains 371254 sequences. (Running on oeis4.)