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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 by T. D. Noe)

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: A018923 A264901 A172418 * A076468 A246550 A197917

Adjacent sequences:  A036964 A036965 A036966 * A036968 A036969 A036970

KEYWORD

easy,nonn,nice

AUTHOR

N. J. A. Sloane.

EXTENSIONS

More terms from Erich Friedman.

Corrected by Vladeta Jovovic, Aug 17 2002

STATUS

approved

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Last modified September 30 06:50 EDT 2016. Contains 276618 sequences.