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A225422 Largest number k such that k < d(k)^(n/10), where d(k) is the number of divisors of k. 0
2, 2, 6, 12, 12, 24, 60, 180, 360, 1260, 5040, 15120, 55440, 166320, 831600, 4324320, 36756720, 367567200, 2327925600, 27935107200 (list; graph; refs; listen; history; text; internal format)
OFFSET

11,1

COMMENTS

Each of these numbers is the product of small primes. For example, a(30) = 2^7 2^3 5^2 7 11 13 17 19. - T. D. Noe, May 16 2013

LINKS

Table of n, a(n) for n=11..30.

MATHEMATICA

Table[last = 0; Do[If[n < DivisorSigma[0, n]^(i/10), last = n], {n, 10^4}]; last, {i, 11, 20}]

CROSSREFS

Cf. A034884 (n < d(n)^2), A056757 (n < d(n)^3), A225729-A225738.

Sequence in context: A219694 A054481 A262501 * A290518 A242882 A157285

Adjacent sequences:  A225419 A225420 A225421 * A225423 A225424 A225425

KEYWORD

nonn

AUTHOR

T. D. Noe, May 15 2013

STATUS

approved

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Last modified August 9 04:39 EDT 2020. Contains 336319 sequences. (Running on oeis4.)