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A003102 Largest number divisible by all numbers < its n-th root.
(Formerly M2139)
1
2, 24, 420, 27720, 720720, 36756720, 5354228880, 481880599200, 25619985190800, 10685862914126400, 876240758958364800, 113035057905629059200, 24792356033967973651200, 9690712164777231700912800, 2364533768205644535022723200, 396059406174445459616306136000 (list; graph; refs; listen; history; internal format)
OFFSET

1,1

REFERENCES

A. Murthy, Some New Smarandache Sequence, Functions and Partitions, Smarandache Notions Journal, Vol. 11, No. 1-2-3, Spring 2000.

A. Murthy, An application of Smarandache LCM sequence and the largest number divisible by all the integers not exceeding the r-th root, Preprint.

N. Ozeki, On the problem 1, 2, 3, ..., [ n^(1/k) ] | n, Journal of the College of Arts and Sciences, Chiba University (Chiba, Japan), Vol. 3, No. 4 (Sept. 1962), pp. 427-431 [ Math. Rev. 30 213(1085) 1965 ].

J. Roberts, Lure of the Integers, Math. Assoc. America, 1992, p. 277.

D. O. Shklyarsky, N. N. Chentsov and I. M. Yaglom, Selected Problems and Theorems in Elementary Mathematics; Problem 78; Mir Publishers, Moscow.

D. L. Silverman, Problem 159, Pi Mu Epsilon Journal, Vol. 4, No. 3, Fall 1965, p. 124.

N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence).

LINKS

T. D. Noe, Table of n, a(n) for n = 1..50

Smarandache web site

FORMULA

It has been shown that a(n) < {p(2n)}^n, where p(2n) is the (2n)-th prime. - Amarnath Murthy (amarnath_murthy(AT)yahoo.com), Apr 26 2001

MATHEMATICA

k=1; lc=1; Table[While[r=Floor[lc^(1/n)]; Union[Mod[lc, Range[r]]]=={0}, k++; good=lc; lc=LCM[lc, k]]; m=2; While[r=Floor[(m*good)^(1/n)]; Union[Mod[m*good, Range[r]]]=={0}, m++ ]; m=m-1; m*good, {n, 50}] - T. D. Noe (noe(AT)sspectra.com), Aug 01 2006

CROSSREFS

Sequence in context: A052670 A052736 A103904 * A052712 A133413 A012236

Adjacent sequences:  A003099 A003100 A003101 * A003103 A003104 A003105

KEYWORD

nonn,nice

AUTHOR

N. J. A. Sloane (njas(AT)research.att.com), H. W. Gould

EXTENSIONS

Corrected and extended by T. D. Noe (noe(AT)sspectra.com), Aug 01 2006

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Last modified February 14 02:58 EST 2012. Contains 205567 sequences.