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a(n) = sum_{i=1..n} prime(i) + product_{i=1..n} prime(i).
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%I #12 Apr 18 2022 15:56:04

%S 4,11,40,227,2338,30071,510568,9699767,223092970,6469693359,

%T 200560490290,7420738135007,304250263527448,13082761331670311,

%U 614889782588491738,32589158477190045111,1922760350154212639510,117288381359406970983771,7858321551080267055879658

%N a(n) = sum_{i=1..n} prime(i) + product_{i=1..n} prime(i).

%H Vincenzo Librandi, <a href="/A228190/b228190.txt">Table of n, a(n) for n = 1..200</a>

%F a(n) = A002110(n+1) + A007504(n).

%e The first term of this sequence is the sum of the first 1 primes plus the product of the first 1 primes. Thus, 2+2 = 4.

%e The second term of this sequence is the sum of the first 2 primes plus the product of the first 2 primes. Thus, (2+3)+(2*3) = 11.

%e Etc..

%t Table[Sum[Prime[i], {i, n}] + Product[Prime[i], {i, n}], {n, 30}] (* _T. D. Noe_, Aug 16 2013 *)

%t Module[{nn=20,pr},pr=Prime[Range[nn]];Accumulate[pr]+FoldList[Times,pr]] (* _Harvey P. Dale_, Apr 18 2022 *)

%K nonn,easy

%O 1,1

%A _Derek Orr_, Aug 15 2013