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%I #28 Jan 12 2023 15:26:04
%S 3,7,9,19,29,99,145,623,3001,6225
%N Numbers n such that 101^n-100 is prime.
%C Related to hyperperfect numbers of a certain form.
%C 101^623-100, a 1249-digit number, has been certified prime with Primo. - _Rick L. Shepherd_, Jun 21 2002
%C a(10) > 6100. - _Michael S. Branicky_, Mar 07 2021
%H 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 Do[ If[ PrimeQ[101^n - 100], Print[n]], {n, 1, 1850}]
%o (PARI) is(n)=ispseudoprime(101^n-100) \\ _Charles R Greathouse IV_, Jun 13 2017
%o (Python)
%o from sympy import isprime
%o def aupto(lim): return [k for k in range(lim+1) if isprime(101**k-100)]
%o print(aupto(625)) # _Michael S. Branicky_, Mar 07 2021
%K nonn,more
%O 1,1
%A _Jud McCranie_
%E Edited and extended by _Robert G. Wilson v_, Jun 18 2002
%E a(9) from _Michael S. Branicky_, Mar 07 2021
%E a(10) from _Michael S. Branicky_, Jan 12 2023
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