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A247178
Primes p with property that the sum of the cubes of the successive gaps between primes <= p is a prime number.
4
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
OFFSET
1,1
LINKS
EXAMPLE
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.
PROG
(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
CROSSREFS
Sequence in context: A239679 A195353 A342184 * A053183 A247955 A026318
KEYWORD
nonn,easy
AUTHOR
Abhiram R Devesh, Nov 22 2014
STATUS
approved