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A139718 A number n is included if |k -n/k| divides n for at least one divisor k of n. 2
2, 6, 8, 12, 18, 20, 24, 30, 32, 36, 42, 48, 50, 54, 56, 60, 72, 80, 90, 96, 98, 108, 110, 120, 128, 132, 140, 144, 150, 156, 162, 168, 180, 182, 192, 200, 210, 216, 224, 240, 242, 252, 270, 272, 288, 294, 300, 306, 320, 324, 336, 338, 342, 350, 360, 378, 380 (list; graph; refs; listen; history; internal format)
OFFSET

1,1

COMMENTS

All terms are even. All positive integers of the form n(n+1) are included.

LINKS

Alexis Olson, Table of n, a(n) for n = 1..526

EXAMPLE

36 is included because 3 is a divisor of 36 and |3 - 36/3| = 9 divides 36.

MATHEMATICA

Contribution from Alexis Olson (AlexisOlson(AT)gmail.com), Nov 14 2008: (Start)

For[n = 1; s = {}, n <= 10000, n++,

..For[i = 1, i <= Length[Divisors[n]], i++, k = Divisors[n][[i]];

....If[Abs[k-n/k]>0&&Mod[n, Abs[k-n/k]==0, s=Union[s, {n}]; Break[]]]]; s (End)

CROSSREFS

Cf. A139719.

Sequence in context: A077561 A008407 A111224 * A173340 A135311 A200568

Adjacent sequences:  A139715 A139716 A139717 * A139719 A139720 A139721

KEYWORD

nonn

AUTHOR

Leroy Quet May 01 2008

EXTENSIONS

More terms from Alexis Olson (AlexisOlson(AT)gmail.com), Nov 14 2008

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Last modified February 14 20:10 EST 2012. Contains 205663 sequences.