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A211889
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Smallest positive d such that prime(n)+k*d is prime for 0 <= k <= n.
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3
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1, 2, 6, 30, 60, 244230, 6930, 546840, 3120613860, 7399357350, 10719893274090, 173761834256010, 14772517344885300
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OFFSET
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1,2
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COMMENTS
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LINKS
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FORMULA
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PROG
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(Haskell)
a211889 n = head [k | let p = a000040 n, k <- [1..],
all ((== 1) . a010051') $ map ((+ p) . (* k)) (a002260_row n)]
(Python)
from sympy import isprime, prime, primorial, primepi
if n == 1:
return 1
delta = primorial(primepi(n))
p, d = prime(n), delta
while True:
q = p
for _ in range(n):
q += d
if not isprime(q):
break
else:
return d
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CROSSREFS
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KEYWORD
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nonn,more
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AUTHOR
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EXTENSIONS
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STATUS
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approved
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