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A239236 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. 1
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 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

The terms in A007088 with a prime number of 1's are trivially contained in this sequence.

LINKS

Table of n, a(n) for n=1..37.

EXAMPLE

1011 is a member of this sequence because 1^1011 + 0^1011 + 1^1011 + 1^1011 = 3 is prime.

PROG

(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

CROSSREFS

Cf. A007088, A239237.

Sequence in context: A225534 A245475 A175963 * A043494 A277959 A278937

Adjacent sequences:  A239233 A239234 A239235 * A239237 A239238 A239239

KEYWORD

nonn,base

AUTHOR

Derek Orr, Mar 13 2014

EXTENSIONS

a(12)-a(37) from Giovanni Resta, Mar 14 2014

STATUS

approved

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Last modified July 9 14:08 EDT 2020. Contains 335543 sequences. (Running on oeis4.)