A119343 Theodorus primes: primes formed from the concatenation of the initial decimal digits of Theodorus's constant, sqrt(3).

17, 173, 1732050807568877293

Offset

1,1

Comments

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

Links

Amiram Eldar, Table of n, a(n) for n = 1..6

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. A002194, A119344.

Sequence in context: A048555 A299331 A173647 * A164744 A228214 A246058

Adjacent sequences: A119340 A119341 A119342 * A119344 A119345 A119346

Keyword

nonn,base

Author

Eric W. Weisstein, May 15 2006

Extensions

Edited by Charles R Greathouse IV, Apr 27 2010

Status

approved