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A112277 Numbers m such that A112276(m) is composite. 2
8, 14, 20, 21, 24, 26, 32, 33, 34, 38, 44, 45, 48, 50, 54, 55, 56, 57, 62, 63, 64, 68, 74, 75, 76, 80, 81, 84, 85, 86, 90, 91, 92, 93, 94, 98, 104, 105, 110, 114, 115, 116, 117, 118, 119, 120, 122, 123, 124, 128, 132, 133, 135, 140, 141, 142, 143, 144, 145, 147, 152 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

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

FORMULA

A000005(a(n)) <= A000005(A112276(a(n))).

A066247(A112276(a(n)) = 1.

MATHEMATICA

f[1] = 1; f[n_] := Module[{m = n + 1, d = DivisorSigma[0, n]}, While[DivisorSigma[0, m] > d, m++]; m]; Select[Range[150], CompositeQ[f[#]] &] (* Amiram Eldar, Feb 03 2020 *)

CROSSREFS

Cf. A000005, A066247, A112276.

Sequence in context: A231718 A212020 A283597 * A078754 A068638 A025044

Adjacent sequences:  A112274 A112275 A112276 * A112278 A112279 A112280

KEYWORD

nonn

AUTHOR

Reinhard Zumkeller, Sep 01 2005

STATUS

approved

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Last modified August 11 02:59 EDT 2020. Contains 336420 sequences. (Running on oeis4.)