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A239236
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Numbers n such that d_1^n + d_2^n + ... + d_k^n is prime where d_i represents the i-th digit in the decimal representation of n.
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1
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11, 101, 110, 111, 353, 1001, 1010, 1011, 1100, 1101, 1110, 10001, 10010, 10011, 10100, 10101, 10110, 11000, 11001, 11010, 11100, 11111, 62315, 100001, 100010, 100011, 100100, 100101, 100110, 101000, 101001, 101010, 101100, 101111, 110000, 110001, 110010
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OFFSET
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1,1
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COMMENTS
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The terms in A007088 with a prime number of 1's are trivially contained in this sequence.
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LINKS
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EXAMPLE
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1011 is a member of this sequence because 1^1011 + 0^1011 + 1^1011 + 1^1011 = 3 is prime.
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PROG
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(Python)
import sympy
from sympy import isprime
def Pow(x):
..num = 0
..for i in str(x):
....num += int(i)**x
..if isprime(num):
....return True
x = 1
while x < 10**5:
..if Pow(x):
....print(x)
..x += 1
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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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