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Integers for which the smallest m in A040076 such that n*2^m+1 is prime (A050921) increases.
7

%I #9 Feb 13 2017 13:34:13

%S 1,3,7,17,19,31,47,383,2897,3061,4847,5359,10223

%N Integers for which the smallest m in A040076 such that n*2^m+1 is prime (A050921) increases.

%C Where records occur in A040076. A103964 gives the record values.

%t a = -1; Do[m = 0; While[ !PrimeQ[n*2^m + 1], m++ ]; If[m > a, a = m; Print[n]], {n, 1, 10^3} ]

%Y Cf. A040076, A050921.

%K more,nonn

%O 1,2

%A _Robert G. Wilson v_, Oct 16 2001

%E Corrected and extended by _T. D. Noe_, Nov 15 2010

%E a(13) was found by PrimeGrid, added by _Arkadiusz Wesolowski_, Feb 13 2017