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 A053810 Prime powers of prime numbers. 37
 4, 8, 9, 25, 27, 32, 49, 121, 125, 128, 169, 243, 289, 343, 361, 529, 841, 961, 1331, 1369, 1681, 1849, 2048, 2187, 2197, 2209, 2809, 3125, 3481, 3721, 4489, 4913, 5041, 5329, 6241, 6859, 6889, 7921, 8192, 9409, 10201, 10609, 11449, 11881, 12167 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS This is to triprimes as A053810 (Prime powers of prime numbers) is to primes and as semiprimes are to A113877 (Semiprimes to semiprime powers). - Jonathan Vos Post, Mar 26 2013 LINKS T. D. Noe, Table of n, a(n) for n = 1..9965 FORMULA a(n) = A053811(n)^A053812(n). - David Wasserman, Feb 17 2006 A010055(a(n)) * A010051(A100995(a(n))) = 1. - Reinhard Zumkeller, Jun 05 2013 Sum_{n>=1} 1/a(n) = Sum_{p prime} P(p) = 0.6716752222..., where P is the prime zeta function. - Amiram Eldar, Nov 21 2020 MATHEMATICA pp={}; Do[if=FactorInteger[n]; If[Length[if]==1&&PrimeQ[if[[1, 1]]]&&PrimeQ[if[[1, 2]]], pp=Append[pp, n]], {n, 13000}]; pp Sort[ Flatten[ Table[ Prime[n]^Prime[i], {n, 1, PrimePi[ Sqrt[12800]]}, {i, 1, PrimePi[ Log[ Prime[n], 12800]]}]]] PROG (PARI) is(n)=isprime(isprimepower(n)) \\ Charles R Greathouse IV, Mar 19 2013 (Haskell) a053810 n = a053810_list !! (n-1) a053810_list = filter ((== 1) . a010051 . a100995) \$ tail a000961_list -- Reinhard Zumkeller, Jun 05 2013 CROSSREFS Cf. A000040, A000961, A053811, A053812. Cf. A203967; subsequence of A000961. Sequence in context: A093771 A051676 A114129 * A076702 A051761 A153326 Adjacent sequences:  A053807 A053808 A053809 * A053811 A053812 A053813 KEYWORD easy,nonn,changed AUTHOR Henry Bottomley, Mar 28 2000 EXTENSIONS More terms from David Wasserman, Feb 17 2006 STATUS approved

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Last modified November 30 21:31 EST 2020. Contains 338813 sequences. (Running on oeis4.)