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%I #18 Sep 08 2022 08:46:08
%S 6,11,37,135,2059,8205,131089,524307,8388631,536870941,2147483679,
%T 137438953509,2199023255593,8796093022251,140737488355375,
%U 9007199254741045,576460752303423547,2305843009213694013,147573952589676412995,2361183241434822606919
%N a(n) = 2^prime(n) + prime(n).
%H Vincenzo Librandi, <a href="/A243139/b243139.txt">Table of n, a(n) for n = 1..200</a>
%H J. Mestel, <a href="/A005605/a005605.pdf">Archimedeans Problems Drive 1977</a>, Eureka, 39 (1978), 38-40. (Annotated scanned copy)
%t f[n_]:=(2^Prime[n] + Prime[n]); Array[f, 80, 1]
%o (Magma) [2^p + p: p in PrimesUpTo(80)];
%Y Cf. A034785, A100105.
%K nonn
%O 1,1
%A _Vincenzo Librandi_, Jun 03 2014