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A247178
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Primes p with property that the sum of the cubes of the successive gaps between primes <= p is a prime number.
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4
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7, 13, 31, 103, 157, 211, 229, 277, 283, 337, 349, 367, 373, 379, 433, 463, 499, 523, 547, 577, 613, 619, 643, 673, 751, 907, 937, 1009, 1021, 1039, 1123, 1201, 1231, 1327, 1399, 1459, 1489, 1543, 1579, 1597, 1669, 1723, 1777, 1789, 1831, 1873, 1933, 1987, 2011, 2017
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OFFSET
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1,1
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LINKS
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EXAMPLE
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a(1)=7; primes less than or equal to 7: [2, 3, 5, 7]; cubes of prime gaps: [1, 8, 8]; sum of squares of prime gaps: 17.
a(2)=13; primes less than or equal to 13: [2, 3, 5, 7, 11, 13]; cubes of prime gaps: [1, 8, 8, 64, 8]; sum of squares of prime gaps: 89.
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PROG
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(Python)
from sympy import nextprime, isprime
p=2
s=0
while 0 < p < 10000:
np=nextprime(p)
if isprime(s):
print(p)
d=np-p
s+=(d*d*d)
p=np
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CROSSREFS
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KEYWORD
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nonn,easy
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AUTHOR
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STATUS
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approved
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