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 A036967 4-full numbers: if a prime p divides n then so does p^4. 11
 1, 16, 32, 64, 81, 128, 243, 256, 512, 625, 729, 1024, 1296, 2048, 2187, 2401, 2592, 3125, 3888, 4096, 5184, 6561, 7776, 8192, 10000, 10368, 11664, 14641, 15552, 15625, 16384, 16807, 19683, 20000, 20736, 23328, 28561, 31104, 32768, 34992 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 COMMENTS a(m) mod prime(n) > 0 for m < A258601(n); a(A258601(n)) = A030514(n) = prime(n)^4. - Reinhard Zumkeller, Jun 06 2015 REFERENCES E. Kraetzel, Lattice Points, Kluwer, Chap. 7, p. 276. LINKS T. D. Noe and Alois P. Heinz, Table of n, a(n) for n = 1..10000, (first 300 terms from T. D. Noe) FORMULA Sum_{n>=1} 1/a(n) = Product_{p prime} (1 + 1/(p^3*(p-1))) = 1.1488462139214317030108176090790939019972506733993367867997411290952527... - Amiram Eldar, Jul 09 2020 MATHEMATICA Join[{1}, Select[Range[35000], Min[Transpose[FactorInteger[#]][[2]]]>3&]] (* Harvey P. Dale, Jun 05 2012 *) PROG (Haskell) import Data.Set (singleton, deleteFindMin, fromList, union) a036967 n = a036967_list !! (n-1) a036967_list = 1 : f (singleton z) [1, z] zs where    f s q4s p4s'@(p4:p4s)      | m < p4 = m : f (union (fromList \$ map (* m) ps) s') q4s p4s'      | otherwise = f (union (fromList \$ map (* p4) q4s) s) (p4:q4s) p4s      where ps = a027748_row m            (m, s') = deleteFindMin s    (z:zs) = a030514_list -- Reinhard Zumkeller, Jun 03 2015 (PARI) is(n)=n==1 || vecmin(factor(n)[, 2])>3 \\ Charles R Greathouse IV, Sep 17 2015 CROSSREFS A030514 is a subsequence. Cf. A001694, A036966, A046101, A258601. Sequence in context: A264901 A339840 A172418 * A076468 A246550 A197917 Adjacent sequences:  A036964 A036965 A036966 * A036968 A036969 A036970 KEYWORD easy,nonn,nice AUTHOR EXTENSIONS More terms from Erich Friedman Corrected by Vladeta Jovovic, Aug 17 2002 STATUS approved

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Last modified May 12 11:51 EDT 2021. Contains 343821 sequences. (Running on oeis4.)