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A101414 Defiant primes of order 3. Primes p such that no prime numerator and denominator of the continued fraction rational approximation of sqrt(p) exist for numerators less than 10^3 digits in length. 0
5, 17, 23, 37, 47, 53, 61, 79, 83, 97, 101 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Defiant primes of order k are also of order r where 0 < r < k.

LINKS

Table of n, a(n) for n=1..11.

EXAMPLE

The 8th convergent of sqrt(5) is c = 51841/23184. c^2 = 5.00000000186... but both numerator and denominator are nonprime.

PROG

(PARI) cfracnumdenomprime(m, f) = { default(realprecision, 3000); cf = vector(m+10); x=f; for(n=0, m, i=floor(x); x=1/(x-i); cf[n+1] = i; ); for(m1=0, m, r=cf[m1+1]; forstep(n=m1, 1, -1, r = 1/r; r+=cf[n]; ); numer=numerator(r); denom=denominator(r); if(ispseudoprime(numer)&&ispseudoprime(denom), print1(numer", "); numer2=numer; denom2=denom); if(length(Str(numer))>999, break); ) }

CROSSREFS

Sequence in context: A067377 A153504 A044438 * A105884 A019410 A133423

Adjacent sequences:  A101411 A101412 A101413 * A101415 A101416 A101417

KEYWORD

frac,nonn,base

AUTHOR

Cino Hilliard, Jan 16 2005

STATUS

approved

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Last modified March 30 10:09 EDT 2020. Contains 333125 sequences. (Running on oeis4.)