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A138403
a(n) = p^3*(p-1), where p = prime(n).
5
8, 54, 500, 2058, 13310, 26364, 78608, 123462, 267674, 682892, 893730, 1823508, 2756840, 3339294, 4775858, 7741604, 11911982, 13618860, 19850358, 25053770, 28009224, 38457042, 46886534, 62037272, 87616608, 103030100, 111458154
OFFSET
1,1
FORMULA
a(n) = A000010(prime(n)^4). - R. J. Mathar, Oct 15 2017
From Amiram Eldar, Nov 22 2022: (Start)
a(n) = prime(n)^4 - prime(n)^3 = A030514(n) - A030078(n).
Product_{n>=1} (1 - 1/a(n)) = A065415. (End)
MATHEMATICA
a = {}; Do[p = Prime[n]; AppendTo[a, p^4 - p^3], {n, 1, 50}]; a
PROG
(PARI) forprime(p=2, 1e3, print1(p^4-p^3", ")) \\ Charles R Greathouse IV, Jun 16 2011
(Magma) [NthPrime((n))^4 - NthPrime((n))^3: n in [1..40] ]; // Vincenzo Librandi, Jun 17 2011
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
Artur Jasinski, Mar 19 2008
STATUS
approved