Smarandache-Wellin prime 

In mathematics, a Smarandache-Wellin number is an integer that in a given base is the concatenation of the first n prime numbers written in that base. Smarandache-Wellin numbers are named after Florentin Smarandache and Paul R. Wellin.

The first decimal Smarandache-Wellin numbers are:

2, 23, 235, 2357, 235711, ... (sequence A019518 in OEIS).

Smarandache-Wellin primes

A Smarandache-Wellin number that is also prime is called a Smarandache-Wellin prime. The first three are 2, 23 and 2357 (A069151). The fourth has 355 digits and ends with the digits 719.1

The primes at the end of the concatenation in the Smarandache-Wellin primes are

2, 3, 7, 719, 1033, 2297, 3037, 11927?, ... (A046284).

The indices of the Smarandache-Wellin primes in the sequence of Smarandache-Wellin numbers are:

1, 2, 4, 128, 174, 342, 435, 1429?, ... (A046035).

The 1429th Smarandache-Wellin number is a probable prime with 5719 digits ending in 11927, discovered by Eric W. Weisstein in 1998.2 If it is proven prime, it will be the eighth Smarandache-Wellin prime. In July 2006 Weisstein's search showed the index of the next Smarandache-Wellin prime (if one exists) is greater than 18272.3

See also

References

  1. ^ Pomerance, Carl B.; Crandall, Richard E. (2001). Prime Numbers: a computational perspective. Springer, p78 Ex 1.86. ISBN 0387252827. 
  2. ^ Rivera, Carlos, Primes by Listing
  3. ^ Eric W. Weisstein, Integer Sequence Primes at MathWorld.