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%I #25 Nov 21 2020 14:03:49
%S 3,5,7,19,31,43,103,223,367,463,5503,738197503
%N Record primes reached in A052333.
%C Start with n=1, take 2n+1, if composite take 2n+1 again, keep going until you reach a prime. Repeat for n=2, 3... If prime is a record, add to sequence. If never reach a prime, skip that value of n.
%C a(13) is a 771-digit prime reached after 2552 iterations starting from 73. - _Warut Roonguthai_. This was proved to be a prime by Paul Jobling (Paul.Jobling(AT)WhiteCross.com) using PrimeForm and by _Ignacio Larrosa Cañestro_ using Titanix (http://www.znz.freesurf.fr/pages/titanix.html). [Oct 30 2000]
%H Amiram Eldar, <a href="/A052334/b052334.txt">Table of n, a(n) for n = 1..13</a>
%F a(n) = A052333(A051914(n)). - _Amiram Eldar_, Jul 25 2019
%t record = 2; Reap[For[n = 1, n <= 100, n++, k = n; While[ !PrimeQ[k = 2*k + 1]]; If[k > record, Print[k]; Sow[k]; record = k]]][[2, 1]] (* _Jean-François Alcover_, Jul 19 2013 *)
%Y Cf. A050412, A051914, A052333, A052339, A052340.
%K nonn,nice
%O 1,1
%A _Christian G. Bower_, Dec 19 1999
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