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A225733 Numbers n such that n < d(n)^(5/2), where d(n) is the number of divisors of n. 1
2, 3, 4, 5, 6, 8, 9, 10, 12, 14, 15, 16, 18, 20, 21, 22, 24, 26, 27, 28, 30, 32, 36, 40, 42, 44, 45, 48, 50, 52, 54, 56, 60, 63, 64, 66, 68, 70, 72, 75, 76, 78, 80, 84, 88, 90, 96, 100, 102, 104, 105, 108, 110, 112, 114, 120, 126, 128, 130, 132, 135, 136, 138 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Alternatively, we could write n^2 < d(n)^5. The last odd number is a(206) = 945.

LINKS

T. D. Noe, Table of n, a(n) for n = 1..1018 (complete sequence)

MATHEMATICA

t = {}; Do[If[n < DivisorSigma[0, n]^(5/2), AppendTo[t, n]], {n, 10^6}]; t

CROSSREFS

Cf. A034884 (n < d(n)^2), A175495 (n < 2^d(n)), A056757 (n < d(n)^3).

Cf. A225729-A225738.

Sequence in context: A225736 A225735 A225734 * A225732 A295585 A324578

Adjacent sequences:  A225730 A225731 A225732 * A225734 A225735 A225736

KEYWORD

nonn,fini,full

AUTHOR

T. D. Noe, May 14 2013

STATUS

approved

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Last modified December 6 16:05 EST 2021. Contains 349565 sequences. (Running on oeis4.)