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a(2*n) = prime(n+1) * prime(n+2), a(2*n-1) = prime(n+1).
1

%I #20 Sep 21 2017 14:21:19

%S 6,3,15,5,35,7,77,11,143,13,221,17,323,19,437,23,667,29,899,31,1147,

%T 37,1517,41,1763,43,2021,47,2491,53,3127,59,3599,61,4087,67,4757,71,

%U 5183,73,5767,79,6557,83,7387,89,8633,97,9797,101,10403,103,11021,107,11663

%N a(2*n) = prime(n+1) * prime(n+2), a(2*n-1) = prime(n+1).

%H G. C. Greubel, <a href="/A116570/b116570.txt">Table of n, a(n) for n = 0..5000</a>

%F a(2*n) = prime(n+1) * prime(n+2). a(2*n-1) = prime(n+1). - _Michael Somos_, Jul 20 2016

%Y Cf. A114557.

%K nonn,less

%O 0,1

%A _Roger L. Bagula_, Mar 18 2006

%E Edited, new name using _Michael Somos_' formula, _Joerg Arndt_, Sep 21 2017