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a(n) = prime(n) * 2^n.
2

%I #13 Sep 08 2022 08:46:14

%S 4,12,40,112,352,832,2176,4864,11776,29696,63488,151552,335872,704512,

%T 1540096,3473408,7733248,15990784,35127296,74448896,153092096,

%U 331350016,696254464,1493172224,3254779904,6777995264,13824425984,28722593792,58518929408,121332826112

%N a(n) = prime(n) * 2^n.

%F a(n) = A000079(n) * A000040(n).

%e a(1) = 4 because prime(1) * 2^1 = 2 * 2 = 4.

%t Array[Prime@# 2^# &, {30}] (* _Michael De Vlieger_, Dec 02 2015 *)

%o (PARI) a(n) = prime(n) * 2^n;

%o (Magma) [NthPrime(n)*2^n: n in [1..30]]; // _Vincenzo Librandi_, Dec 03 2015

%Y Cf. A000040, A000079.

%Y Equals twice A110295. - _David Radcliffe_, Dec 03 2015

%K nonn,easy

%O 1,1

%A _Altug Alkan_, Dec 02 2015