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A119343
Theodorus-primes: primes formed from the concatenation of the initial decimal digits of Theodorus's constant, sqrt(3).
5
17, 173, 1732050807568877293
OFFSET
1,1
COMMENTS
The next term (a(4)) has 111 digits. - Harvey P. Dale, Oct 24 2014
LINKS
Eric Weisstein's World of Mathematics, Theodorus-Prime
Eric Weisstein's World of Mathematics, Integer Sequence Primes
EXAMPLE
sqrt(3) = 1.732050807568877..., 17--the concatenation of the first 2 decimal digits--is prime, so a(1)=17.
MATHEMATICA
nn=300; With[{ds3=RealDigits[Sqrt[3], 10, nn][[1]]}, Select[ Table[ FromDigits[ Take[ds3, n]], {n, nn}], PrimeQ]] (* Harvey P. Dale, Oct 24 2014 *)
CROSSREFS
Cf. A119344.
Sequence in context: A048555 A299331 A173647 * A164744 A228214 A246058
KEYWORD
nonn,bref,base
AUTHOR
Eric W. Weisstein, May 15 2006
EXTENSIONS
Edited by Charles R Greathouse IV, Apr 27 2010
STATUS
approved