OFFSET
1,1
LINKS
Robert Israel, Table of n, a(n) for n = 1..300
FORMULA
a(n) = 5*10^(n-1) + A124049(n) for n > 1. - Robert Israel, Jan 12 2025
MAPLE
f:= proc(n) local t, p;
p:= 5*10^(n-1);
do
p:= nextprime(p);
if isprime(10^n - p) then return p fi
od
end proc:
map(f, [$1..30]); # Robert Israel, Jan 13 2025
PROG
(PARI) a(n) = local(t); n=10^n; t=nextprime(n/2+1); while(!isprime(n-t), t=nextprime(t+1)); t \\ Charles R Greathouse IV, Sep 29 2008
CROSSREFS
KEYWORD
nonn,base
AUTHOR
Lekraj Beedassy, Jan 29 2008
EXTENSIONS
a(7)-a(30) from Charles R Greathouse IV, Sep 29 2008
More terms from Michel Marcus, Jan 13 2025
STATUS
approved
