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A244926
Numbers m such that there is an integer k with the property that antisigma(m) = k * sigma(m) + k.
1
1, 2, 247, 2279, 9167, 57479, 200479, 518039, 2119207, 3685439, 9240079, 16384279, 31536647, 101601359, 140558807, 189771287, 299142967, 354032447, 384150199, 486103279, 565468637, 802008239, 853795074, 1107541759, 1328438479, 1494742004, 1580837719, 1768013279
OFFSET
1,2
COMMENTS
Numbers m such that A244329(m) = floor(antisigma(m) / sigma(m)) = antisigma(m) mod sigma(m) = A232324(n).
Corresponding values of integers k: 0, 0, 108, 1092, 4488, 28500, 99792, 258300, 1058148, ...
Numbers m such that sigma(m) + 1 divides antisigma(m). - Kevin P. Thompson, Nov 27 2021
LINKS
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))]
(PARI) isok(m) = my(s=sigma(m)); denominator((m*(m+1)/2-s)/(s+1)) == 1; \\ Michel Marcus, Jan 21 2022
CROSSREFS
Cf. A024816 (antisigma), A000203 (sigma), A244329, A232324.
Sequence in context: A145712 A259141 A065664 * A024031 A099685 A027653
KEYWORD
nonn
AUTHOR
Jaroslav Krizek, Jul 08 2014
EXTENSIONS
a(10)-a(28) from Kevin P. Thompson, Nov 27 2021
STATUS
approved