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a(n) = prime(n) * prime(n^2) - prime(n^3).
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%I #9 Sep 10 2017 14:58:47

%S 2,2,12,60,376,642,1550,2238,4118,7770,9534,15846,21966,26490,35750,

%T 46934,63204,73164,94248,112812,128922,161128,185576,225062,278260,

%U 315108,347596,393898,426998,478078,614064,682998,769800,827466,962166,1036806,1156866,1286448,1390878,1534754

%N a(n) = prime(n) * prime(n^2) - prime(n^3).

%C All terms are even.

%C For prime(n)^3 - prime(n^3) see A262199.

%C For prime(n)^3 - prime(n) * prime(n^2) see A291542.

%C For PrimePi(n^3) - PrimePi(n) * PrimePi(n^2) see A291539.

%F A291542(n) + a(n) = A262199(n).

%e a(2) = prime(2) * prime(4) - prime(8) = 3*7 - 19 = 2.

%t Table[ Prime[n] * Prime[n^2] - Prime[n^3], {n, 40}]

%o (PARI) a(n) = prime(n) * prime(n^2) - prime(n^3); \\ _Michel Marcus_, Sep 10 2017

%Y Cf. A000720, A123914, A262199, A291440, A291538, A291539, A291540, A291542.

%K nonn

%O 1,1

%A _Jonathan Sondow_, Aug 25 2017