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A138407 a(n) = p^4*(p-1), where p = prime(n). 5

%I #24 Nov 22 2022 02:33:44

%S 16,162,2500,14406,146410,342732,1336336,2345778,6156502,19803868,

%T 27705630,67469796,113030440,143589642,224465326,410305012,702806938,

%U 830750460,1329973986,1778817670,2044673352,3038106318,3891582322

%N a(n) = p^4*(p-1), where p = prime(n).

%H Vincenzo Librandi, <a href="/A138407/b138407.txt">Table of n, a(n) for n = 1..200</a>

%H <a href="/index/Pri#prime_powers">Index to sequences related to prime powers</a>.

%F a(n) = A000010(prime(n)^5). - _R. J. Mathar_, Oct 15 2017

%F From _Amiram Eldar_, Nov 22 2022: (Start)

%F a(n) = prime(n)^5 - prime(n)^4 = A050997(n) - A030514(n).

%F Product_{n>=1} (1 - 1/a(n)) = A065416. (End)

%t a = {}; Do[p = Prime[n]; AppendTo[a, p^5 - p^4], {n, 1, 50}]; a

%t f54[n_]:=Module[{c=Prime[n]},c^5-c^4]; Array[f54,30] (* _Harvey P. Dale_, Mar 29 2015 *)

%o (PARI) forprime(p=2,1e3,print1(p^5-p^4", ")) \\ _Charles R Greathouse IV_, Jun 16 2011

%o (Magma) [NthPrime((n))^5 - NthPrime((n))^4: n in [1..30] ]; // _Vincenzo Librandi_, Jun 17 2011

%Y Cf. A000010, A030514, A050997, A065416.

%K nonn,easy

%O 1,1

%A _Artur Jasinski_, Mar 19 2008

%E First Mathematica program corrected by _Harvey P. Dale_, Mar 29 2015

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Last modified April 25 05:18 EDT 2024. Contains 371964 sequences. (Running on oeis4.)