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a(n) = p^5 - p^3 + p^2, where p = prime(n).
1

%I #13 Sep 08 2022 08:45:32

%S 28,225,3025,16513,159841,369265,1415233,2469601,6424705,20487601,

%T 28600321,69294673,115788961,146930785,229243393,418049425,714722401,

%U 844373041,1349828833,1803876481,2072687905,3076569601,3938475745,5583362401,8586436993,10509080401,11591658625,14024303713,15384956401

%N a(n) = p^5 - p^3 + p^2, where p = prime(n).

%H Vincenzo Librandi, <a href="/A135180/b135180.txt">Table of n, a(n) for n = 1..1000</a>

%F p=A000040(n): a(n) = p^5 - p^3 + p^2.

%e a(4)=16513 because the 4th prime number is 7, 7^5 = 16807, 7^3 = 343, 7^2 = 49 and 16807 - 343 + 49 = 16513.

%t #^5 - #^3 + #^2 &/@Prime[Range[40]] (* _Vincenzo Librandi_, May 22 2014 *)

%o (Magma)[p^5-p^3+p^2: p in PrimesUpTo(200)]; // _Vincenzo Librandi_, Dec 14 2010

%Y Cf. p^2: A001248. p^3: A030078. p^5: A050997.

%K nonn,easy

%O 1,1

%A _Omar E. Pol_, Nov 25 2007

%E More terms from _Vincenzo Librandi_, Dec 14 2010