OFFSET
1,2
REFERENCES
C. Caldwell and H. Dubner, "Journal of Recreational Mathematics", Volume 28, No. 1, 1996-97, pp. 1-9.
LINKS
Patrick De Geest, World!Of Numbers, Palindromic Wing Primes (PWP's)
Makoto Kamada, Prime numbers of the form 99...99199...99
FORMULA
a(n) = (A077776(n)-1)/2.
MATHEMATICA
Do[If[PrimeQ[10^(2n + 1) - 8*10^n - 1], Print[n]], {n, 3000}]
PROG
(PARI) is(n)=ispseudoprime(10^(2*n+1)-8*10^n-1) \\ Charles R Greathouse IV, Jun 13 2017
CROSSREFS
KEYWORD
nonn,base
AUTHOR
Ray Chandler, Dec 28 2010
EXTENSIONS
Added one more term from PWP table, by Patrick De Geest, Nov 05 2014
STATUS
approved