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A229090 Numbers n such that sigma(n) mod n > antisigma(n) mod n, where sigma(n) = A000203(n) = sum of divisors of n, antisigma(n) = A024816(n) = sum of non-divisors of n. 5
2, 8, 10, 12, 15, 16, 21, 24, 30, 32, 42, 44, 45, 50, 52, 60, 63, 64, 68, 75, 76, 80, 92, 99, 105, 110, 116, 117, 124, 126, 128, 130, 135, 136, 140, 144, 147, 148, 150, 152, 153, 154, 160, 164, 165, 168, 170, 171, 172, 182, 184, 188, 189, 190, 195, 198, 200 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Numbers n such that A229087(n) = A000203(n) mod n - A024816(n) mod n = A054024(n) - A229110(n) > 0.

Complement of union A229088 and A229089 with respect to A000027, where A229088 = numbers n such that sigma(n) mod n = antisigma(n) mod n, A229089 = numbers n such that sigma(n) mod n < antisigma(n) mod n.

LINKS

Jaroslav Krizek, Table of n, a(n) for n = 1..10000

EXAMPLE

Number 12 is in sequence because sigma(12) mod 12 = 28 mod 12 = 4 > antisigma(12) mod 12 = 50 mod 12 = 2.

MATHEMATICA

smQ[n_]:=Module[{sig=DivisorSigma[1, n]}, Mod[sig, n]>Mod[(n(n+1))/2-sig, n]]; Select[Range[200], smQ] (* Harvey P. Dale, Dec 23 2013 *)

CROSSREFS

Cf. A000203 (sigma(n)), A024816 (antisigma(n)).

Cf. A054024 (sigma(n) mod n), A229110 (antisigma(n) mod n).

Sequence in context: A084124 A081693 A022298 * A265670 A297999 A287088

Adjacent sequences:  A229087 A229088 A229089 * A229091 A229092 A229093

KEYWORD

nonn

AUTHOR

Jaroslav Krizek, Oct 24 2013

STATUS

approved

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Last modified April 14 01:45 EDT 2021. Contains 342941 sequences. (Running on oeis4.)