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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 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

The next term (a(4)) has 111 digits. - Harvey P. Dale, Oct 24 2014

LINKS

Table of n, a(n) for n=1..3.

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

Adjacent sequences:  A119340 A119341 A119342 * A119344 A119345 A119346

KEYWORD

nonn,bref,base

AUTHOR

Eric W. Weisstein, May 15 2006

EXTENSIONS

Edited by Charles R Greathouse IV, Apr 27 2010

STATUS

approved

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Last modified April 7 19:42 EDT 2020. Contains 333306 sequences. (Running on oeis4.)