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%I #19 Oct 17 2024 12:16:01
%S 0,1,2,5,7,8,14,29,43,52,62,259,302,638,1100,1139,1607,2125,2210,4843,
%T 4969,5605,9967,10849,11603,22247,43120,55250,66023,108044,378418,
%U 429715,628892,699133,1488109,1510687,3486295,6733457,10498004,12018290
%N a(n) = A139480(n)/2.
%H Amiram Eldar, <a href="/A139481/b139481.txt">Table of n, a(n) for n = 2..48</a>
%F a(n) = A146768(n-1)-1. - _R. J. Mathar_, Mar 30 2011
%t (MersennePrimeExponent[Range[2, 48]] - 3)/2 (* _Amiram Eldar_, Oct 17 2024 *)
%Y Cf. A000043, A000668, A124477, A139479, A139480, A146768.
%K nonn,less
%O 2,3
%A _Artur Jasinski_, Apr 22 2008
%E Edited by _N. J. A. Sloane_, May 23 2008