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a(n) = prime(n) * 3^prime(n) - 1.
0

%I #19 Sep 08 2022 08:45:15

%S 17,80,1214,15308,1948616,20726198,2195382770,22082967872,

%T 2165293113020,1990280943581606,19147875284802356,

%U 16660504517966902430,1495392851464002242522,14115049597965094337960,1249674274871002654525988,1027312020387041054530226318

%N a(n) = prime(n) * 3^prime(n) - 1.

%e a(1) = 2*3^2 - 1 = 17.

%t Do[Print[Prime[n]*3^(Prime[n]) - 1], {n, 1, 20}] (* _Stefan Steinerberger_, Feb 15 2006 *)

%t # 3^#-1&/@Prime[Range[20]] (* _Harvey P. Dale_, Jan 24 2012 *)

%o (Magma) [NthPrime(n)*3^NthPrime(n) - 1: n in [1..20]]; // _Vincenzo Librandi_, Aug 27 2015

%Y Cf. A060352.

%K nonn

%O 1,1

%A _Parthasarathy Nambi_, Dec 07 2004

%E More terms from _Stefan Steinerberger_, Feb 15 2006

%E a(15)-a(16) from _Vincenzo Librandi_, Aug 27 2015