OFFSET
1,1
LINKS
Robert Israel, Table of n, a(n) for n = 1..9999
FORMULA
a(n) <= A168421(n+1) - 2, with equality for n = 6, 263, 3061, 4750, 4893, 5029, 5555, 6101, ....
EXAMPLE
a(3) = 11 because there are exactly 3 primes between 11 and 22, namely 13, 17 and 19, and 11 is the least prime that works.
MAPLE
V:= Vector(100, -1): p:= 1:
for n from 1 while p < 727 do # note that A168421(101) = 727
p:= nextprime(p);
v:= numtheory:-pi(2*p)-n;
if v <= 100 and V[v] = -1 then
V[v]:= p;
fi
od:
convert(V, list);
CROSSREFS
KEYWORD
sign
AUTHOR
J. M. Bergot and Robert Israel, Jul 29 2022
STATUS
approved