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Record values in A040076.
8

%I #17 Jul 17 2019 07:29:25

%S 0,1,2,3,6,8,583,6393,9715,33288,3321063,5054502,31172165

%N Record values in A040076.

%C The index sequence of this sequence is 1, 3, 7, 17, 19, 31, 47, 383, 2897. A040076(2897)>8192, not yet found.

%C A064699 gives where the records occur.

%e A040076(1)=0, so a(1)=0;

%e A040076(3)=1, so a(2)=1;

%t k = -1; n = 0; km = k; While[k < 8192, n++; k = 0; cp = n*(2^ k) + 1; While[(! PrimeQ[cp]) && (k < 8192), k++; cp = n*(2^k) + 1]; If[k > km, km = k; Print[{n, km}]]]

%Y Cf. A040076, A103963.

%K nonn,more

%O 1,3

%A _Lei Zhou_, Feb 24 2005

%E Extended by _T. D. Noe_, Nov 15 2010

%E a(13) was found by PrimeGrid, added by _Richard N. Smith_, Jul 15 2019