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%I #9 Jun 14 2014 21:31:29
%S 971,12641,205607,228341,276557,412343,1012217,1101323,1902881,
%T 2171021,2477411,2692121,4116377,4311677,6060953,6182993,6388913,
%U 6444863,8341121,8551451,9507527,10523141,10997411,11444093,14101361,14656307,14813147,15435587,17337521
%N Primes p for which p^i - 4 is prime for i = 1, 3, 5 and 7.
%C Subsequence of A243818: Primes p for which p^i - 4 is prime for i = 1, 3 and 5.
%H Abhiram R Devesh, <a href="/A243861/b243861.txt">Table of n, a(n) for n = 1..100</a>
%e Prime p=971 is in this sequence because p-4 = 967 (prime), p^3-4 = 915498607 (prime), p^5-4 = 863169625893847 (prime), and p^7-4 = 813831713247384370687 (prime).
%o (Python)
%o import sympy.ntheory as snt
%o n=2
%o while n>1:
%o ....n1=n-4
%o ....n2=((n**3)-4)
%o ....n3=((n**5)-4)
%o ....n4=((n**7)-4)
%o ....##Check if n1 , n2, n3 and n4 are also primes.
%o ....if snt.isprime(n1)== True and snt.isprime(n2)== True and snt.isprime(n3)== True and snt.isprime(n4)== True:
%o ........print(n, n1, n2, n3, n4)
%o ....n=snt.nextprime(n)
%Y Cf. A023200, A243583, A243780, A243818.
%K nonn,easy
%O 1,1
%A _Abhiram R Devesh_, Jun 12 2014