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A146360
Primes p such that continued fraction of (1 + sqrt(p))/2 has period 15: primes in A146338.
37
193, 281, 1861, 1933, 2089, 2141, 2437, 2741, 2837, 3037, 3121, 3413, 4001, 4637, 4877, 5821, 6653, 7673, 8117, 10069, 10273, 10457, 11197, 11549, 11821, 12409, 13037, 14653, 15061, 15077, 18661, 20549, 22921, 23117, 24169, 25621, 28837, 35597, 35869, 36389, 38569
OFFSET
1,1
LINKS
MAPLE
A146326 := proc(n) if not issqr(n) then numtheory[cfrac]( (1+sqrt(n))/2, 'periodic', 'quotients') ; nops(%[2]) ; else 0 ; fi; end: isA146360 := proc(n) RETURN(isprime(n) and A146326(n) = 15) ; end: for n from 2 to 30000 do if isA146360(n) then printf("%d, \n", n) ; fi; od: # R. J. Mathar, Sep 06 2009
MATHEMATICA
Select[Prime[Range[1500]], Length[ContinuedFraction[(Sqrt[#]+1)/2][[2]]] == 15&] (* Harvey P. Dale, Aug 16 2014 *)
KEYWORD
nonn
AUTHOR
Artur Jasinski, Oct 30 2008
EXTENSIONS
8539 removed by R. J. Mathar, Sep 06 2009
More terms from Amiram Eldar, Mar 30 2020
STATUS
approved