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A185695
Final prime adjoined in the smallest term of A019518 divisible by 61^n.
1
23, 41719, 308537, 270907253, 28643801327
OFFSET
1,1
COMMENTS
Associated with A019518(i) at i = 9, 4363, 26688, 14758114, ...
PROG
(Python)
from sympy import nextprime
def A185695(n):
p, k, m = 2, 61**n, 10
q, m2 = p % k, m % k
while True:
p = nextprime(p)
while p >= m:
m *= 10
m2 = m % k
q = (q*m2 + p) % k
if q == 0:
return p # Chai Wah Wu, May 01 2020
KEYWORD
nonn,base,more
AUTHOR
James G. Merickel, Feb 05 2011
EXTENSIONS
a(5) from Chai Wah Wu, May 01 2020
STATUS
approved