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Primes p such that p - 1 is a binary Keith number (A162724).
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%I #11 Dec 23 2015 14:20:56

%S 2,3,5,17,257,1367,65537,2960687

%N Primes p such that p - 1 is a binary Keith number (A162724).

%C See A162724 (binary Keith numbers) and A007629 (Keith numbers) for definitions.

%C Primes of the form A162724(n)+1.

%C Fermat primes (A019434) are terms.

%C The next term, if it exists, must be greater than 17*10^9.

%C Union of primes p of the form A162363(n)+1 and A000079(m)+1 for a some n or m.

%t fQ[n_] := Module[{b = IntegerDigits[n, 2], s}, s = Total@ b; If[s <= 1, True, k = 1; While[s = 2 s - b[[k]]; s < n, k++]; s == n]]; Select[Prime@ Range[10^6], fQ[# - 1] &] (* _Michael De Vlieger_, Dec 09 2015, after _T. D. Noe_ at A162724 *)

%Y Cf. A000079, A007629, A019434, A162363, A162724.

%K nonn,more

%O 1,1

%A _Jaroslav Krizek_, Dec 08 2015