A271512 - OEIS

%I #26 Sep 08 2022 08:46:16

%S 10,20,56,120,364,560,1140,1540,2600,4960,5984,9880,13244,15180,19600,

%T 27720,37820,41664,54740,64824,70300,88560,102340,125580,161700,

%U 182104,192920,215820,227920,253460,357760,392084,447580,467180,573800,596904,669920,748660

%N a(n) = (p+1)*(p+2)*(p+3)/6 where p is the n-th prime.

%C Subsequence of A000292.

%H Vincenzo Librandi, <a href="/A271512/b271512.txt">Table of n, a(n) for n = 1..1000</a>

%F a(n) = A000292(A000040(n)+1). - _Michel Marcus_, Apr 10 2016

%p A271512:=n->(ithprime(n)+1)*(ithprime(n)+2)*(ithprime(n)+3)/6: seq(A271512(n), n=1..80); # _Wesley Ivan Hurt_, Apr 10 2016

%t Table[(Prime[n]^3 + 6 Prime[n]^2 + 11 Prime[n] + 6) / 6, {n, 50}]

%o (Magma) [(p+1)*(p+2)*(p+3) / 6: p in PrimesUpTo(200)];

%o (Python)

%o from sympy import prime

%o for n in range(1,1000):

%o     p=prime(n)

%o     print((int)(((p+1)*(p+2)*(p+3))/6))

%o # _Soumil Mandal_, Apr 11 2016

%o (PARI) lista(nn) = forprime(p=2, nn, print1((p+1)*(p+2)*(p+3)/6, ", ")); \\ _Altug Alkan_, Apr 10 2016

%Y Cf. A000040, A000292, A271511.

%K nonn,easy

%O 1,1

%A _Vincenzo Librandi_, Apr 10 2016