A046284 - OEIS

A046284

Primes p such that concatenation of primes from 2 through p is a prime.

2, 3, 7, 719, 1033, 2297, 3037, 11927

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OFFSET

1,1

COMMENTS

"w_n = (P_1)(P_2) ... (P_n) [A019518], by which notation we mean that w_n is constructed in decimal by simple concatenation of digits [much like the Almost Natural numbers (A007376)]. For example, the first few w_n are 2, 23, 235, 2357, 235711, ... ." - Crandall and Pomerance

REFERENCES

R. Crandall and C. Pomerance, Prime Numbers: A Computational Perspective, Springer, NY, 2001; see p. 72. [The 2002 printing states incorrectly that 5441 is a term.]

LINKS

Table of n, a(n) for n=1..8.

Eric Weisstein's World of Mathematics, Consecutive Number Sequences.

Eric Weisstein's World of Mathematics, Integer Sequence Primes

Eric Weisstein's World of Mathematics, Smarandache-Wellin Number

EXAMPLE

7 is a member, since 2357 is a prime.

MATHEMATICA

a = ""; Do[a = StringJoin[a, ToString[ Prime[n]]]; If[ PrimeQ[ ToExpression[a]], Print[n]], {n, 1, 1429}]

CROSSREFS

Cf. A019518, A033308, A069151. a(n) = prime(A046035(n)).

Sequence in context: A062615 A180162 A129907 * A077524 A069503 A238400