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A082092 Composite k such that d(k) < d(sigma(k)), i.e., A000005(k) < A000005(A000203(k)). 1
6, 10, 14, 15, 20, 21, 22, 24, 26, 27, 28, 30, 33, 34, 35, 38, 39, 40, 42, 44, 45, 46, 49, 51, 54, 55, 56, 57, 58, 60, 62, 63, 65, 66, 68, 69, 70, 74, 76, 77, 78, 82, 85, 86, 87, 88, 91, 92, 93, 94, 95, 96, 99, 102, 104, 105, 106, 108, 110, 111, 114, 115, 116, 117, 118, 119 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Not identical with A069116.

LINKS

Amiram Eldar, Table of n, a(n) for n = 1..10000

EXAMPLE

For n=27: d(27)=4, sigma(27) = 1 + 3 + 9 + 27 = 40, d(40) = 8 > d(27);

27 is not in A069116.

MATHEMATICA

df[x_] := Sign[ -DivisorSigma[0, x]+DivisorSigma[0, DivisorSigma[1, x]]] Do[s=df[n]; If[Equal[s, 1]&&!PrimeQ[n], Print[n]], {n, 1, 1000}]

CROSSREFS

Cf. A000005, A000203, A037197, A069116, A073803, A073804.

Sequence in context: A080364 A325230 A227299 * A069116 A063763 A115956

Adjacent sequences:  A082089 A082090 A082091 * A082093 A082094 A082095

KEYWORD

nonn

AUTHOR

Labos Elemer, Apr 10 2003

STATUS

approved

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Last modified March 3 03:03 EST 2021. Contains 341756 sequences. (Running on oeis4.)