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A244926 Numbers n such that there is an integer k with the property that antisigma(n) = k * sigma(n) + k. 0
1, 2, 247, 2279, 9167, 57479, 200479, 518039, 2119207 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

Antisigma(n) = A024816(n) = the sum of the nondivisors of n that are between 1 and n, sigma(n) = A000203(n) = the sum of the divisors of n.

Numbers n such that A244329(n) = floor(antisigma(n) / sigma(n)) = antisigma(n) mod sigma(n) = A232324(n).

Corresponding values of integers k: 0, 0, 108, 1092, 4488, 28500, 99792, 258300, 1058148, …

LINKS

Table of n, a(n) for n=1..9.

EXAMPLE

247 is in sequence because 30348 = antisigma(247) = 108 * sigma(247) + 108 = 108*280 + 108.

PROG

(MAGMA) [n: n in [1..100000] | Floor(((n*(n+1)div 2) - (SumOfDivisors(n))) div (SumOfDivisors(n))) eq ((n*(n+1)div 2) - (SumOfDivisors(n))) mod (SumOfDivisors(n))]

CROSSREFS

Cf. A024816, A000203, A244329, A232324.

Sequence in context: A145712 A259141 A065664 * A024031 A099685 A027653

Adjacent sequences:  A244923 A244924 A244925 * A244927 A244928 A244929

KEYWORD

nonn

AUTHOR

Jaroslav Krizek, Jul 08 2014

STATUS

approved

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Last modified July 29 10:30 EDT 2021. Contains 346344 sequences. (Running on oeis4.)