OFFSET
1,2
COMMENTS
The sequence is infinite. Indeed, by [Sierpiński] (see also Theorem 21 in [Trost]) for given decimal digits c_1..c_m such that c_m equals 1,3,7 or 9, there are infinitely many primes ending with c_1..c_m.
REFERENCES
W. Sierpiński, Sur l'existence de nombres premiers avec une suite arbitraire de chiffres initiaux, Le Matematiche Catania, 1951.
E. Trost, Primzahlen, Verlag Birkhäuser, 1953, Theorems 20 - 21.
EXAMPLE
Let n=6. Since a(5)=2113, then, omitting 2, we obtain the number 113 whose reverse is s=311. The smallest prime ending with 311 is 2311. So a(6)=2311.
CROSSREFS
KEYWORD
nonn,base
AUTHOR
Vladimir Shevelev, Sep 20 2015
STATUS
approved