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A067129
Numbers n such that sigma(n-3) + sigma(n+3) = sigma(2n).
1
5, 63, 99, 279, 355, 551, 561, 639, 1359, 1915, 2151, 2799, 4311, 8199, 8919, 10915, 12591, 13239, 16265, 16911, 17991, 18999, 20799, 24039, 24471, 28071, 28719, 30519, 33039, 35271, 40671, 43479, 45351, 48879, 51623, 52911, 56799, 60471, 63351, 74079, 75879
OFFSET
1,1
COMMENTS
Conjecture: sequence gives odd values only.
LINKS
PROG
(PARI) isok(n) = sigma(n-3)+sigma(n+3) == sigma(2*n); \\ Michel Marcus, Nov 20 2013
CROSSREFS
Cf. A067730.
Sequence in context: A319624 A182118 A111387 * A209117 A238087 A063079
KEYWORD
nonn
AUTHOR
Benoit Cloitre, Feb 18 2002
EXTENSIONS
More terms from Michel Marcus, Nov 20 2013
STATUS
approved