OFFSET
1,1
LINKS
Robert Israel, Table of n, a(n) for n = 1..10000 (first 126 terms from R. J. Mathar)
EXAMPLE
Primes pertaining to i=19 are 191, 193, 197, 199, 1913. (1911, 1915, 1917, etc. are composite.)
For i=1 and 2 there are no such primes.
MAPLE
f:= proc(n) local R, d, t, tm;
R:= NULL;
for d from 1 to ilog10(n)+1 do
t:= 10^d*n + 10^(d-1)-1;
if d = ilog10(n)+1 then tm:= (10^d + 1)*n else tm:= 10^d*(n+1) fi;
do
t:= nextprime(t);
if t >= tm then break fi;
R:= R, t;
od;
od;
R
end proc:
map(f, [$1..40]); # Robert Israel, Aug 04 2020
CROSSREFS
KEYWORD
AUTHOR
Amarnath Murthy, Aug 04 2005
EXTENSIONS
More terms from R. J. Mathar, Feb 21 2008
STATUS
approved