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%I #15 Feb 22 2024 20:23:43
%S 3,4,7,9,17,15,29,25,35,35,59,43,77,55,65,71,111,73,127,89,109,107,
%T 161,107,167,137,163,143,215,131,239,183,207,191,237,187,307,223,255,
%U 225,351,217,371,263,285,277,409,275,407,299,363,327,479,311,429,351,419
%N a(n) = prime(phi(n)) + phi(prime(n)).
%C I made this up to demonstrate how easy it is to construct dull but unguessable sequences with short descriptions.
%H G. C. Greubel, <a href="/A048849/b048849.txt">Table of n, a(n) for n = 1..10000</a>
%p with(numtheory); [ seq(ithprime(phi(i))+phi(ithprime(i)),i=1..80) ];
%t Table[Prime[EulerPhi[n]] + EulerPhi[Prime[n]], {n,100}] (* _G. C. Greubel_, Feb 22 2024 *)
%o (Magma) [NthPrime(EulerPhi(n)) + EulerPhi(NthPrime(n)) : n in [1..100]]; // _G. C. Greubel_, Feb 22 2024
%o (SageMath) [nth_prime(euler_phi(n)) + euler_phi(nth_prime(n)) for n in range(1,101)] # _G. C. Greubel_, Feb 22 2024
%Y Cf. A000010, A000040, A048848.
%K nonn,easy
%O 1,1
%A _N. J. A. Sloane_
%E Offset corrected by _G. C. Greubel_, Feb 22 2024
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