A124262 a(1) = 2; for n > 1, a(n) is largest prime < 10*a(n-1).

2, 19, 181, 1801, 17989, 179849, 1798487, 17984833, 179848309, 1798483067, 17984830667, 179848306667, 1798483066669, 17984830666651, 179848306666507, 1798483066665031, 17984830666650269, 179848306666502647

Offset

1,1

Links

Charles R Greathouse IV, Table of n, a(n) for n = 1..1000, extending and correcting a b-file from Artur Jasinski

Mathematica

NestList[NextPrime[10 #, -1]&, 2, 20] (* Vincenzo Librandi, Jun 28 2014 *)

Prog

(PARI) step(k)=precprime(10*k)
t=1/5; vector(10, n, t=step(t)) \\ Charles R Greathouse IV, Sep 14 2015

Crossrefs

Cf. A006902, A040016, A120031-A120040, A126041.

Sequence in context: A037637 A163067 A221904 * A140781 A128970 A218117

Adjacent sequences: A124259 A124260 A124261 * A124263 A124264 A124265

Keyword

nonn

Author

Artur Jasinski, Dec 16 2006

Status

approved