A055492 - OEIS

A055492

Numbers n such that LCM{1, ..., n} is a minimal number.

1, 2, 3, 4, 5, 6, 8, 9, 10, 11, 12, 16, 27, 28

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OFFSET

1,2

COMMENTS

Minimal numbers (A007416): let A(h) = least positive integer having exactly h divisors, let d(n) = number of divisors of n; then n is minimal if A(d(n)) = n; i.e. if n is the least positive integer having the number of divisors it has.

Also the numbers n such that LCM (1, ..., n) is a highly composite number (A002182). - Matthew Vandermast, Jul 12 2004

REFERENCES

J. Roberts, Lure of the Integers, Math. Assoc. of America, 1992, page 86.

LINKS

Table of n, a(n) for n=1..14.

M. E. Grost, The smallest number with a given number of divisors, Amer. Math. Monthly, 75 (1968), 725-729.

CROSSREFS

Cf. A007416.

Cf. A003418, A095921.

Sequence in context: A031143 A358521 A302594 * A005459 A039216 A336109

Adjacent sequences: A055489 A055490 A055491 * A055493 A055494 A055495

KEYWORD

nonn,fini,full

AUTHOR

Robert G. Wilson v, Jul 05 2000

EXTENSIONS

Description corrected by N. J. A. Sloane, Feb 27 2003

STATUS

approved