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a(n) is the smallest number such that if x >= a(n), then pi^*(x) - pi^*(x/2) >= n, where pi^*(x) is the number of terms of A050376 <= x.
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%I #14 Sep 03 2013 06:04:10

%S 2,3,11,16,23,41,47,59,67,71,79,101,107,109,127,149,167,169,179,181,

%T 227,229,233,239,256,263,269,281,283,307,347,349,359,367,373,401,409,

%U 419,431,433,439,461,487,491,521,569,587,593,599,601,607,617,641,643,647

%N a(n) is the smallest number such that if x >= a(n), then pi^*(x) - pi^*(x/2) >= n, where pi^*(x) is the number of terms of A050376 <= x.

%C The sequence is a Fermi-Dirac analog of Ramanujan numbers (A104272), since terms of A050376 play a role of primes in Fermi-Dirac arithmetic (see comments in A050376).

%H Peter J. C. Moses, <a href="/A228520/b228520.txt">Table of n, a(n) for n = 1..10000</a>

%F a(n)<= R_n, where R_n is the n-th Ramanujan number (A104272); a(n)~A000040(2*n) as n goes to infinity.

%Y Cf. A104272.

%K nonn

%O 1,1

%A _Vladimir Shevelev_, Aug 24 2013

%E More terms from _Peter J. C. Moses_