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Central terms of the triangle in A116366.
2

%I #23 Mar 22 2023 14:43:11

%S 6,12,20,30,42,54,62,76,90,102,116,130,144,154,166,190,200,218,234,

%T 246,260,276,288,320,330,342,358,372,384,408,424,448,456,486,500,516,

%U 536,550,570,588,602,624,636,654,662,690,714,730,750,774,796,810,828,850,864,882,890,918,928

%N Central terms of the triangle in A116366.

%H G. C. Greubel, <a href="/A116368/b116368.txt">Table of n, a(n) for n = 1..10000</a>

%F a(n) = A000040(2n) + A000040(n+1).

%F a(n) = A116366(2*n-1, n).

%e For n=4, prime(2n) = prime(8) = 19, and prime(n+1) = prime(5) = 11, so a(4) = 19 + 11 = 30. - _Michael B. Porter_, Aug 15 2016

%t Table[Prime[2n] + Prime[n+1], {n, 1, 70}](* _Terry D. Grant_, Aug 15 2016 *)

%o (PARI) vector(70, n, prime(2*n) + prime(n+1)) \\ _G. C. Greubel_, May 18 2019

%o (Magma) [NthPrime(2*n) + NthPrime(n+1): n in [1..70]]; // _G. C. Greubel_, May 18 2019

%o (Sage) [nth_prime(2*n) + nth_prime(n+1) for n in (1..70)] # _G. C. Greubel_, May 18 2019

%o (GAP) List([1..70], n-> Primes[2*n] + Primes[n+1]) # _G. C. Greubel_, May 18 2019

%Y Cf. A000040, A116366.

%K nonn

%O 1,1

%A _Reinhard Zumkeller_, Feb 06 2006