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 A048945 Numbers n such that product of divisors of n is a fourth power. 4
 1, 24, 30, 40, 42, 54, 56, 66, 70, 78, 88, 102, 104, 105, 110, 114, 120, 128, 130, 135, 136, 138, 152, 154, 165, 168, 170, 174, 182, 184, 186, 189, 190, 195, 210, 216, 222, 230, 231, 232, 238, 246, 248, 250, 255, 256, 258, 264, 266, 270, 273, 280, 282, 285 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 COMMENTS Different from sequence of numbers which are the cube root of the product of their proper divisors. Compare A111398. REFERENCES Amarnath Murthy, Generalization of Partition function, Introducing Smarandache Factor partitions, Smarandache Notions Journal, Vol. 11, 1-2-3, Spring 2000. Amarnath Murthy, A note on Smarandache Divisor Sequence, Introducing Smarandache Factor partitions, Smarandache Notions Journal, Vol. 11, 1-2-3, Spring 2000. Amarnath Murthy, Some more ideas on Smarandache Factor Partitions, Smarandache Notions Journal, Vol. 11, 1-2-3, Spring 2000. LINKS Charles R Greathouse IV, Table of n, a(n) for n = 1..10000 Eric Weisstein's World of Mathematics, Divisor Product MAPLE for n from 2 to 1000 do it1 := sort(convert(divisors(n), list)): it2 := product(it1[j], j=1..nops(it1)-1): if it2 = n^3 then printf(`%d, `, n) fi: od: MATHEMATICA Select[Range[300], IntegerQ[(Times @@ Divisors[#])^(1/4)] &] (* Jean-François Alcover, Nov 05 2012 *) PROG (PARI) is(n)=my(f=factor(n)[, 2]); gcd(f)*prod(i=1, #f, f[i]+1)%8==0 \\ Charles R Greathouse IV, Sep 18 2015 CROSSREFS Cf. A111398, A111399. Sequence in context: A292982 A109797 A129656 * A111398 A030626 A302571 Adjacent sequences:  A048942 A048943 A048944 * A048946 A048947 A048948 KEYWORD nonn AUTHOR STATUS approved

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Last modified April 3 00:35 EDT 2020. Contains 333195 sequences. (Running on oeis4.)