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A048945 Numbers n such that product of divisors of n is a fourth power. 2
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; 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

M. L. Perez et al., eds., Smarandache Notions Journal

Eric Weisstein's World of Mathematics, Link to a section of The World of Mathematics.

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:

CROSSREFS

Cf. A111398, A111399.

Sequence in context: A068544 A109797 A129656 * A111398 A030626 A125639

Adjacent sequences:  A048942 A048943 A048944 * A048946 A048947 A048948

KEYWORD

nonn

AUTHOR

Eric Weisstein (eric(AT)weisstein.com)

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Last modified February 17 10:05 EST 2012. Contains 206009 sequences.