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%I #18 Jul 04 2021 14:47:10
%S 30,38,66,110,144,156,164,174,194,210,222,230,266,278,282,318,354,374,
%T 392,432,474,528,540,552,588,630,636,650,704,714,716,812,918,960,1076,
%U 1086,1122,1142,1190,1224,1322,1362,1388,1394,1418,1452,1506,1508,1532,1538,1596
%N Numbers k such that k^7 - k^6 - k^5 - k^4 - k^3 - k^2 - k - 1 is prime.
%C Every term is even.
%e 30^7 - 30^6 - 30^5 - 30^4 - 30^3 - 30^2 - 30 - 1 = 21115862069 is prime. Thus 30 is a member of this sequence.
%t Select[Range[1600],PrimeQ[#^7-Total[#^Range[0,6]]]&] (* _Harvey P. Dale_, Jul 04 2021 *)
%o (Python)
%o import sympy
%o from sympy import isprime
%o {print(n, end=', ') for n in range(10**3) if isprime(n**7-n**6-n**5-n**4-n**3-n**2-n-1)}
%o (PARI) for(n=1, 10^3, if(ispseudoprime(n^7-sum(i=0, 6, n^i)), print1(n, ", ")))
%K nonn
%O 1,1
%A _Derek Orr_, Jun 03 2014
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