A054902 Composite numbers n such that sigma(n)+12 = sigma(n+12).

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

Donovan Johnson, Table of n, a(n) for n = 1..500

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.

Cf. A015913-A015917, A023200, A023203, A046133, A001359, A054799.

Sequence in context: A326157 A044397 A044778 * A255244 A261989 A051968

Adjacent sequences: A054899 A054900 A054901 * A054903 A054904 A054905

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