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A228324
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Primes arising from A228323 in order of their appearance.
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2
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13, 23, 29, 59, 521, 421, 47, 67, 613, 1013, 1019, 1619, 1627, 827, 811, 1511, 1523, 1223, 1217, 2017, 2029, 1429, 1433, 2633, 2647, 1847, 1831, 2531, 2539, 2239, 2237, 2437, 2441, 3041, 3049, 3449, 3457, 2857, 2843, 3643, 3659, 3259, 3251, 3851, 3853, 4253
(list;
graph;
refs;
listen;
history;
text;
internal format)
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OFFSET
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1,1
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REFERENCES
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Eric Angelini, Posting to the Sequence Fans Mailing List, Aug 14 2013.
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LINKS
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PROG
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(Python)
from sympy import isprime
from itertools import islice
def c(s, t):
u, v = int(s+t), int(t+s)
if isprime(u): return u
if isprime(v): return v
return False
def agen():
aset, k, mink = set(), 1, 2
while True:
an = k; aset.add(an); s, k = str(an), mink
while k in aset or not c(s, str(k)): k += 1
while mink in aset: mink += 1
yield c(s, str(k))
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CROSSREFS
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KEYWORD
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nonn,base
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AUTHOR
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EXTENSIONS
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STATUS
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approved
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