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 A074661 Let n = 2^e_2 * 3^e_3 * 5^e_5 * ... be the prime factorization of n; sequence gives n such that max{e_2, e_3, ...} is prime. 3
 4, 8, 9, 12, 18, 20, 24, 25, 27, 28, 32, 36, 40, 44, 45, 49, 50, 52, 54, 56, 60, 63, 68, 72, 75, 76, 84, 88, 90, 92, 96, 98, 99, 100, 104, 108, 116, 117, 120, 121, 124, 125, 126, 128, 132, 135, 136, 140, 147, 148, 150, 152, 153, 156, 160, 164, 168, 169, 171, 172, 175, 180, 184 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS The old entry with this sequence number was a duplicate of A056594. The largest exponent of the prime factors of n is prime. - Harvey P. Dale, Mar 09 2012 LINKS MATHEMATICA Select[Range[200], PrimeQ[Max[Transpose[FactorInteger[#]][[2]]]]&] (* Harvey P. Dale, Mar 09 2012 *) PROG (PARI) isA074661(n) = if(n<4, 0, isprime(vecmax(factor(n)[, 2]))) CROSSREFS Cf. A096432, A060476. Sequence in context: A319302 A119025 A167903 * A252849 A082293 A048944 Adjacent sequences:  A074658 A074659 A074660 * A074662 A074663 A074664 KEYWORD nonn AUTHOR N. J. A. Sloane, Sep 18 2008 STATUS approved

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Last modified December 15 11:43 EST 2019. Contains 329999 sequences. (Running on oeis4.)