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 A121267 Number of decimal digits in A047777(n). 3
 1, 5, 1, 3, 1, 2, 1, 4, 3057, 2, 3, 14650, 4, 2, 46, 4 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 COMMENTS Not equal to the first differences of A053013 (which is based on a different variant of A047777). "A new visitor to an old problem! Jens Kruse Andersen confirmed the primality of Nash's 3057-digit prime using PRIMO." - Carlos Rivera, Sep 2002. LINKS Carlos Rivera, Problem 18. Pi as a concatenation of the smallest contiguous different primes, The Prime Puzzles & Problems Connection. PROG (PARI) default(realprecision, 5000); c=Pi/10; u=[]; for(k=1, 9e9, ispseudoprime(c\.1^k) & !setsearch(u, c\.1^k) & (u=setunion(u, Set(c\.1^k))) & !print1(k, ", ") & k=0*c=frac(c*10^k)) \\ - M. F. Hasler, Sep 15 2013 CROSSREFS Cf. A047777, A053013. Sequence in context: A134568 A198798 A229181 * A111740 A327921 A155059 Adjacent sequences:  A121264 A121265 A121266 * A121268 A121269 A121270 KEYWORD nonn,base,more AUTHOR Robert G. Wilson v, Aug 23 2006 EXTENSIONS The old values a(10) onwards were incorrect, as discovered by M. F. Hasler, Aug 31 2013. The old values, the b-file and the Mathematica program have been deleted. - N. J. A. Sloane, Sep 01 2013 STATUS approved

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Last modified December 7 20:40 EST 2021. Contains 349589 sequences. (Running on oeis4.)