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A054902
Composite numbers n such that sigma(n)+12 = sigma(n+12).
6
65, 170, 209, 1394, 3393, 4407, 4556, 11009, 13736, 27674, 38009, 38845, 47402, 76994, 157994, 162393, 184740, 186686, 209294, 680609, 825359, 954521, 1243574, 2205209, 3515609, 4347209, 5968502, 6539102, 6916241, 8165294, 10352294, 10595009, 10786814
OFFSET
1,1
LINKS
EXAMPLE
n = 65, sigma(65)+12 = 84+12 = 96 = sigma(65+12) = sigma(77).
n = 11009, sigma(11009)+12 = 11220+12 = 11232 = sigma(11009+12) = sigma(11021).
PROG
(PARI) isok(n) = !isprime(n) && ((sigma(n)+12) == sigma(n+12)); \\ Michel Marcus, Dec 18 2013
CROSSREFS
Complement of A046133 with respect to A015917.
Sequence in context: A326157 A044397 A044778 * A255244 A261989 A051968
KEYWORD
nonn
AUTHOR
Labos Elemer, May 23 2000
EXTENSIONS
More terms from Jud McCranie, May 24 2000
Three more terms from Michel Marcus, Dec 18 2013
STATUS
approved