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A124184 Positive integers not divisible by any of their own prime-factorization exponents. 1
1, 8, 9, 25, 32, 49, 64, 81, 121, 125, 128, 169, 225, 243, 289, 343, 361, 441, 512, 529, 625, 729, 841, 961, 1000, 1024, 1089, 1225, 1331, 1369, 1521, 1681, 1849, 2025, 2048, 2187, 2197, 2209, 2401, 2601, 2744, 2809, 3025, 3249, 3481, 3721, 3969, 4096, 4225 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

If n>1 is a term then n is composite and is not squarefree. - Farideh Firoozbakht, Dec 08 2006

LINKS

Table of n, a(n) for n=1..49.

EXAMPLE

18225 = 3^6 * 5^2. Neither 6 nor 2 divides 18225, so 18225 is in the sequence.

MATHEMATICA

f[n_] := Times @@ Mod[n, Last /@ FactorInteger[n]] > 0; Select[Range[5000], f] (*Chandler*)

Do[a = FactorInteger[n]; l = Length[a]; b = Table[a[[k]][[2]], {k, l}]; If[ ! MemberQ[Mod[n, b], 0], Print[n]], {n, 4000}] - Farideh Firoozbakht, Dec 08 2006

CROSSREFS

Cf. A124438.

Sequence in context: A068435 A302554 A124438 * A062307 A114130 A130100

Adjacent sequences:  A124181 A124182 A124183 * A124185 A124186 A124187

KEYWORD

nonn

AUTHOR

Leroy Quet, Dec 05 2006

EXTENSIONS

Extended by Ray Chandler and Zak Seidov, Dec 06 2006

STATUS

approved

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Last modified September 21 00:17 EDT 2019. Contains 327252 sequences. (Running on oeis4.)