A138424 a(n) = (prime(n)^5 - prime(n))/2.

15, 120, 1560, 8400, 80520, 185640, 709920, 1238040, 3218160, 10255560, 14314560, 34671960, 57928080, 73504200, 114672480, 209097720, 357462120, 422298120, 675062520, 902114640, 1036535760, 1538528160, 1969520280, 2792029680

Offset

1,1

Links

Vincenzo Librandi, Table of n, a(n) for n = 1..200

Formula

a(n) = A138404(n)/2. - R. J. Mathar, Oct 15 2017

Mathematica

a = {}; Do[p = Prime[n]; AppendTo[a, (p^5 - p)/2], {n, 1, 50}]; a
(#^5-#)/2&/@Prime[Range[30]] (* Harvey P. Dale, Oct 01 2017 *)

Prog

(Magma) [(NthPrime((n))^5 - NthPrime((n)))/2: n in [1..30] ]; // Vincenzo Librandi, Jun 18 2011
(PARI) forprime(p=2, 1e3, print1((p^5-p)/2", ")) \\ Charles R Greathouse IV, Jul 15 2011

Crossrefs

Sequence in context: A022580 A321950 A081079 * A279267 A357602 A120794

Adjacent sequences: A138421 A138422 A138423 * A138425 A138426 A138427

Keyword

nonn,easy

Author

Artur Jasinski, Mar 19 2008

Status

approved