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A152085 a(n) = A152084(n) + 2^floor(log_2(A152084(n))). 2

%I #10 Mar 15 2024 07:26:51

%S 5,11,19,47,73,79,131,137,167,173,191,277,307,367,379,563,569,587,593,

%T 653,677,719,743,1033,1069,1129,1153,1171,1213,1231,1321,1399,1423,

%U 1453,1459,1483,1489,1531,2063,2087,2111,2141,2153,2237,2273,2351,2423,2447

%N a(n) = A152084(n) + 2^floor(log_2(A152084(n))).

%C Every term is prime.

%C If a(n) is written in binary, then the leftmost 2 digits are "10". If the leftmost "10" is replaced with "1", then we would have the binary representation of A152084(n), which is a prime.

%H Robert Israel, <a href="/A152085/b152085.txt">Table of n, a(n) for n = 1..10000</a>

%p filter:= n -> isprime(n) and isprime(n + 2^ilog2(n)):

%p map(t -> t + 2^ilog2(t), select(filter, [seq(i,i=3..10000,2)])); # _Robert Israel_, Mar 14 2024

%Y A152084

%K nonn,changed

%O 1,1

%A _Leroy Quet_, Nov 23 2008

%E Extended by _Ray Chandler_, Nov 26 2008

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Last modified March 28 09:04 EDT 2024. Contains 371240 sequences. (Running on oeis4.)