Location via proxy:   [ UP ]  
[Report a bug]   [Manage cookies]                
A053583
a(n+1) is the smallest prime ending with (but not equal to) a(n), where a(1)=3.
10
3, 13, 113, 2113, 12113, 612113, 11612113, 1611612113, 111611612113, 1111611612113, 81111611612113, 2181111611612113, 132181111611612113, 11132181111611612113, 3411132181111611612113, 413411132181111611612113, 12413411132181111611612113
OFFSET
1,1
LINKS
Michael S. Branicky, Table of n, a(n) for n = 1..370 (terms 1..210 from Robert Israel)
MAPLE
A[1]:= 3;
for n from 2 to 100 do
d:= 10^(ilog10(A[n-1])+1);
for k from 1 do
p:= A[n-1]+d*k;
if isprime(p) then
A[n]:= p;
break
fi
od
od:
seq(A[n], n=1..100); # Robert Israel, Jul 15 2014
PROG
(Python)
from sympy import isprime
from itertools import count, islice
def agen(an=3):
while True:
yield an
pow10 = 10**len(str(an))
for t in count(pow10+an, step=pow10):
if isprime(t):
an = t
break
print(list(islice(agen(), 17))) # Michael S. Branicky, Jun 23 2022
CROSSREFS
KEYWORD
base,nonn
AUTHOR
G. L. Honaker, Jr., Jan 18 2000
EXTENSIONS
Definition corrected by Robert Israel, Jul 15 2014
STATUS
approved