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

16, 162, 2500, 14406, 146410, 342732, 1336336, 2345778, 6156502, 19803868, 27705630, 67469796, 113030440, 143589642, 224465326, 410305012, 702806938, 830750460, 1329973986, 1778817670, 2044673352, 3038106318, 3891582322

Offset: 1

Author

Artur Jasinski, Mar 19 2008

Keywords

• nonn
• easy

Links

• Vincenzo Librandi, Table of n, a(n) for n = 1..200
• Index to sequences related to prime powers.

Crossrefs

Cf. A000010, A030514, A050997, A065416.

Programs

Magma

[NthPrime((n))^5 - NthPrime((n))^4: n in [1..30] ]; // Vincenzo Librandi, Jun 17 2011

Mathematica

a = {}; Do[p = Prime[n]; AppendTo[a, p^5 - p^4], {n, 1, 50}]; a
f54[n_]:=Module[{c=Prime[n]},c^5-c^4]; Array[f54,30] (* Harvey P. Dale, Mar 29 2015 *)

PARI

forprime(p=2,1e3,print1(p^5-p^4", ")) \\ Charles R Greathouse IV, Jun 16 2011

Formula

a(n) = A000010(prime(n)^5). - R. J. Mathar, Oct 15 2017

From Amiram Eldar, Nov 22 2022: (Start)

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

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

Extensions

First Mathematica program corrected by Harvey P. Dale, Mar 29 2015