

A101700


Numbers of the form 3*(10^n3), where 10^n3 is prime.


6




OFFSET

1,1


COMMENTS

a(5) = 3*(10^1403) is 141 digits long and is too large to include.
If m is in this sequence then phi(m)=r(m), so this sequence is a subsequence of A069215. a(n)=3*(10^A089675(n)3), so a(4)=3*(10^173), a(5)=3*(10^1403), a(6)=3*(10^9903), a(7)=3*(10^18873), a(8)=3*(10^35303), a(9)=3*(10^59963), a(10)=3*(10^138203), a(11)=3*(10^218733) & a(12)=3*(10 ^260453).


LINKS



FORMULA



EXAMPLE

299999999999999991 is in the sequence because (10^173) is prime and 3*(10^173)=299999999999999991.


MATHEMATICA

Do[If[PrimeQ[10^n3], Print[3*(10^n3)]], {n, 150}]


CROSSREFS



KEYWORD

nonn


AUTHOR



STATUS

approved



