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a(n) = ((n-th prime)^5-(n-th prime)^3)/24.
3

%I #11 Oct 15 2017 10:17:26

%S 1,9,125,686,6655,15379,58956,102885,267674,853615,1191640,2887221,

%T 4824470,6122039,9551716,17418609,29779955,35182055,56242681,75161310,

%U 86361774,128190140,164102869,232639770,357767816,437877925,482985334

%N a(n) = ((n-th prime)^5-(n-th prime)^3)/24.

%H Harvey P. Dale, <a href="/A138438/b138438.txt">Table of n, a(n) for n = 1..1000</a>

%F a(n) = A138406(n)/24 = A138437(n)/2. - _R. J. Mathar_, Oct 15 2017

%t a = {}; Do[p = Prime[n]; AppendTo[a, (p^5 - p^3)/24], {n, 1, 50}]; a

%t (#^5-#^3)/24&/@Prime[Range[40]] (* _Harvey P. Dale_, May 21 2017 *)

%o (PARI) forprime(p=2,1e3,print1((p^5-p^3)/24", ")) \\ _Charles R Greathouse IV_, Jul 15 2011

%K nonn,easy

%O 1,2

%A _Artur Jasinski_, Mar 19 2008