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A141138 a(n) = prime(A028815(n) - 1) - 1.

%I A141138 #19 Aug 05 2024 08:40:42
%S A141138 1,2,4,10,16,30,40,58,66,82,108,126,156,178,190,210,240,276,282,330,
%T A141138 352,366,400,430,460,508,546,562,586,598,616,708,738,772,796,858,876,
%U A141138 918,966,990,1030,1062,1086,1152,1170,1200,1216,1296,1408,1432,1446,1470
%N A141138 a(n) = prime(A028815(n) - 1) - 1.
%H A141138 G. C. Greubel, <a href="/A141138/b141138.txt">Table of n, a(n) for n = 0..10000</a>
%F A141138 a(n) = A000040(A000040(n)) - 1, with a(0) = 1. - _G. C. Greubel_, Aug 05 2024
%t A141138 A141138[n_]:= If[n==0, 1, Prime[Prime[n]] -1];
%t A141138 Table[A141138[n], {n,0,70}] (* _G. C. Greubel_, Aug 05 2024 *)
%o A141138 (Magma)
%o A141138 A141138:= func< n | n eq 0 select 1 else NthPrime(NthPrime(n)) -1 >;
%o A141138 [A141138(n): n in [0..50]]; // _G. C. Greubel_, Aug 05 2024
%o A141138 (SageMath)
%o A141138 def A141138(n): return 1 if n==0 else nth_prime(nth_prime(n))-1
%o A141138 [A141138(n) for n in range(71)] # _G. C. Greubel_, Aug 05 2024
%Y A141138 Cf. A028815, A141130, A141132, A141133, A141136.
%K A141138 nonn
%O A141138 0,2
%A A141138 _Juri-Stepan Gerasimov_, Jul 31 2008
%E A141138 a(14), a(28) corrected by _D. S. McNeil_, Mar 21 2009
%E A141138 Offset changed by _G. C. Greubel_, Aug 05 2024