OFFSET
1,2
COMMENTS
Corresponding primes are in A061242.
No terms in this sequence end with 2 or 7 (18n-1 ends with 5 when the last digit of n is 2 or 7). - David Garber, Jun 25 2015
LINKS
Zak Seidov, Table of n, a(n) for n = 1..1000
MATHEMATICA
Select[Range[200], PrimeQ[18#-1]&] (* Harvey P. Dale, Mar 09 2011 *)
PROG
(Python)
from gmpy2 import divexact, t_mod
from sympy import prime
A138918 = [divexact(p+1, 18) for p in (prime(n) for n in range(1, 10**6)) if not t_mod(p+1, 18)] # Chai Wah Wu, Sep 02 2014
(PARI) for(n=1, 10^3, if(isprime(18*n-1), print1(n, ", "))) \\ Derek Orr, Sep 03 2014
(Magma) [n: n in [0..150] | IsPrime(18*n-1)]; // Vincenzo Librandi, Jun 27 2015
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
Zak Seidov, Apr 03 2008
STATUS
approved