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A110781
Number of digits in A110780(n).
14
2, 5, 9, 10, 38, 47, 1279, 11389
OFFSET
1,1
COMMENTS
a(8) > 8000. - Michael S. Branicky, Aug 24 2022
PROG
(Python)
from sympy import isprime
from itertools import count, islice
def agen(): # generator of terms
s = ""
while True:
for d in "19":
for k in count(1):
if isprime(int(s+d*k)): break
yield k
s += d*k
print(list(islice(agen(), 7))) # Michael S. Branicky, Aug 24 2022
CROSSREFS
KEYWORD
base,nonn,more
AUTHOR
Amarnath Murthy, Aug 12 2005
EXTENSIONS
More terms from Joshua Zucker, Jan 11 2006
a(7) from Sean A. Irvine, Mar 22 2010
a(8) from Michael S. Branicky, Jun 24 2023
STATUS
approved