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%I #24 Sep 08 2022 08:45:31
%S 1,3,7,11,19,23,31,35,43,55,59,71,79,83,91,103,115,119,131,139,143,
%T 155,163,175,191,199,203,211,215,223,251,259,271,275,295,299,311,323,
%U 331,343,355,359,379,383,391,395,419,443,451,455,463,475,479,499,511,523,535,539,551,559,563,583,611
%N a(n) = 2*prime(n) - 3.
%C Right border of triangle A131424.
%F a(n) = 2*A000040(n) - 3.
%e a(4) = 11 = 2*p(4) - 3 = 2*7 - 3.
%p A131426:=n->2*ithprime(n)-3: seq(A131426(n), n=1..70); # _Wesley Ivan Hurt_, Mar 30 2015
%t 2#-3&/@Prime[Range[80]] (* _Harvey P. Dale_, Jul 24 2011 *)
%o (Magma) [2*NthPrime(n) - 3: n in [1..65]]; // _Vincenzo Librandi_, Mar 30 2015
%o (PARI) a(n) = 2*prime(n) - 3 \\ _Charles R Greathouse IV_, Jul 12 2016
%Y Cf. A000040, A062709, A131424.
%K nonn,easy
%O 1,2
%A _Gary W. Adamson_, Jul 10 2007
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