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%I #15 Nov 16 2023 07:44:02
%S 2,4,11,21,31,110,124,185,279,399,716,1028,4552,6207,6543,11424,11557,
%T 12251,16199,23043,43390,155798,203095,457523,699782,865318,1294026,
%U 2918851,5635889,6459777,8999147,9213126,22383796,28194383,32131750,105097565,404165580
%N Where records occur in A001917.
%H Amiram Eldar, <a href="/A152597/b152597.txt">Table of n, a(n) for n = 1..47</a>
%F a(n) = A000720(A226216(n)). - _Amiram Eldar_, Nov 16 2023
%e First few terms of A001917 (has offset 2) are 1, 1, 2, 1, 1, 2, 1, 2, 1, 6, so a(1) to a(3) are 2, 4, 11.
%o (Magma) W:=[]; r:=0; for n in [2..100000] do p:=NthPrime(n); a:=(p-1)/Modorder(2, p); if r lt a then r:=a; Append(~W,n); end if; end for; print W;
%o (Python)
%o from itertools import islice
%o from sympy import nextprime, n_order
%o def agen():
%o record, v, p = -1, 1, 3
%o while True:
%o if v > record: record = v; yield record
%o v, p = (p-1)//n_order(2, p), nextprime(p)
%o print(list(islice(agen(), 20))) # _Michael S. Branicky_, Oct 09 2022
%Y Cf. A001917 ((p-1)/x, where p = prime(n) and x = smallest positive integer such that 2^x == 1 mod p), A152598 (records in A001917), A000720, A226216.
%K nonn
%O 1,1
%A _Klaus Brockhaus_, Dec 09 2008
%E a(27)-a(37) from _Amiram Eldar_, Mar 08 2019
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