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%I A034926 #32 Jun 08 2024 15:41:27
%S A034926 3,7,9,19,29,99,145,623,3001,6225,23163
%N A034926 Numbers k such that 101^k-100 is prime.
%C A034926 Related to hyperperfect numbers of a certain form.
%C A034926 101^623-100, a 1249-digit number, has been certified prime with Primo. - _Rick L. Shepherd_, Jun 21 2002
%C A034926 a(10) > 6100. - _Michael S. Branicky_, Mar 07 2021
%H A034926 J. S. McCranie, <a href="https://cs.uwaterloo.ca/journals/JIS/VOL3/mccranie.html">A study of hyperperfect numbers</a>, J. Int. Seqs. Vol. 3 (2000) #P00.1.3.
%t A034926 Do[ If[ PrimeQ[101^n - 100], Print[n]], {n, 1, 1850}]
%o A034926 (PARI) is(n)=ispseudoprime(101^n-100) \\ _Charles R Greathouse IV_, Jun 13 2017
%o A034926 (Python)
%o A034926 from sympy import isprime
%o A034926 def aupto(lim): return [k for k in range(lim+1) if isprime(101**k-100)]
%o A034926 print(aupto(625)) # _Michael S. Branicky_, Mar 07 2021
%K A034926 nonn,more
%O A034926 1,1
%A A034926 _Jud McCranie_
%E A034926 Edited and extended by _Robert G. Wilson v_, Jun 18 2002
%E A034926 a(9) from _Michael S. Branicky_, Mar 07 2021
%E A034926 a(10) from _Michael S. Branicky_, Jan 12 2023
%E A034926 a(11) from _Michael S. Branicky_, Jun 08 2024

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