A138421 a(n) = (prime(n)^4 - prime(n)^2)/6.
2, 12, 100, 392, 2420, 4732, 13872, 21660, 46552, 117740, 153760, 312132, 470680, 569492, 812912, 1314612, 2018980, 2307020, 3357772, 4234440, 4732152, 6490640, 7908572, 10455720, 14753312, 17341700, 18756712, 21844692, 23524380, 27172432
Offset: 1
Links
- Vincenzo Librandi, Table of n, a(n) for n = 1..200
Programs
-
Magma
[(NthPrime((n))^4 - NthPrime((n))^2)/6: n in [1..35] ]; // Vincenzo Librandi, Jun 17 2011
-
Mathematica
a = {}; Do[p = Prime[n]; AppendTo[a, (p^4 - p^2)/6], {n, 1, 50}]; a -
PARI
forprime(p=2,1e3,print1((p^4-p^2)/6", ")) \\ Charles R Greathouse IV, Jul 15 2011
Formula
a(n) = A138402(n)/6. - R. J. Mathar, Oct 15 2017