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a(n) = prime(n)*prime(n+1) + prime(n) + prime(n+1).
4

%I #17 Mar 05 2024 14:45:45

%S 11,23,47,95,167,251,359,479,719,959,1215,1595,1847,2111,2591,3239,

%T 3719,4215,4895,5327,5919,6719,7559,8819,9995,10607,11231,11879,12539,

%U 14591,16895,18215,19319,20999,22799,24015,25911,27551,29231,31319,32759

%N a(n) = prime(n)*prime(n+1) + prime(n) + prime(n+1).

%F a(n) = A180617(n) - 1. - _Omar E. Pol_, Dec 08 2019

%t f[n_] := Block[{p = Prime[n], q = Prime[n + 1]}, p*q + p + q]; Array[f, 42] (* _Robert G. Wilson v_, Mar 09 2007 *)

%t Times@@#+Total[#]&/@Partition[Prime[Range[50]],2,1] (* _Harvey P. Dale_, Nov 01 2017 *)

%Y Cf. A000040, A001043, A006094, A126148, A096342, A180617.

%K easy,nonn

%O 1,1

%A _Jonathan Vos Post_, Mar 08 2007

%E More terms from _Robert G. Wilson v_, Mar 09 2007