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%I #4 Aug 24 2020 23:25:54
%S 3,7,31,127,8191,131071,524287,2147483647,4432676798593,
%T 2305843009213693951,57912614113275649087721,
%U 618970019642690137449562111,162259276829213363391578010288127,170141183460469231731687303715884105727,79638304766856507377778616296087448490695649
%N A336719 with duplicates removed.
%C Also, record values in A005420.
%C Mersenne primes (A000668) are a subsequence.
%C For the corresponding orders of 2 (exponents), see A336721.
%o (PARI) re=0;for(k=2,+oo,p=vecmax(factor(2^k-1)[,1]);if(p>re,re=p;print1(re,", ")))
%Y Cf. A000668, A005420, A336719, A336721.
%K nonn
%O 1,1
%A _Jeppe Stig Nielsen_, Aug 01 2020