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A240083 Numbers n such that k^n-(k-1)^n-...-3^n-2^n is prime for some k. 1
1, 2, 3, 4, 5, 10, 11, 13, 15, 16, 17, 18, 19, 21, 22, 24, 26, 27, 28, 29, 31, 32, 33, 35, 41, 45, 46, 47, 48, 49, 53, 55, 57, 58, 59, 61, 65, 67, 71, 76, 82, 83, 87, 88, 89, 91, 93, 94, 99, 101, 103, 107, 108, 110, 111, 114, 115, 116, 119, 123, 127, 130, 132, 134, 138, 141 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

Also numbers n such that A239472(n) > 0.

LINKS

Table of n, a(n) for n=1..66.

PROG

(Python)

import sympy

from sympy import isprime

def Lep(n):

..for k in range(2*10**3):

....num = k**n

....for i in range(2, k):

......num -= i**n

......if num < 0:

........return None

....if isprime(num):

......return k

n = 1

while n < 10**3:

..if Lep(n) != None:

....print(n)

..n += 1

(PARI) a(n)=k=1; while((s=k^n-sum(i=2, k-1, i^n))>0, if(isprime(s), return(k)); k++)

for(n=1, 100, if(a(n), print1(n, ", "))) \\ Derek Orr, Mar 12 2015

CROSSREFS

Cf. A239472.

Sequence in context: A089964 A210495 A179302 * A066996 A126427 A032860

Adjacent sequences:  A240080 A240081 A240082 * A240084 A240085 A240086

KEYWORD

nonn

AUTHOR

Derek Orr, Mar 31 2014

STATUS

approved

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Last modified May 28 01:48 EDT 2020. Contains 334671 sequences. (Running on oeis4.)