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A135245
Aliquot predecessors with the largest degrees.
3
0, 0, 4, 9, 0, 25, 8, 49, 15, 14, 21, 121, 35, 169, 33, 12, 55, 289, 65, 361, 91, 20, 85, 529, 143, 46, 133, 28, 187, 841, 161, 961, 247, 62, 253, 24, 323, 1369, 217, 81, 391, 1681, 341, 1849, 403, 86, 493, 2209, 551, 40, 481, 0, 667, 2809, 533, 106, 703, 68, 697, 3481
OFFSET
1,3
COMMENTS
Find each node's predecessors in aliquot sequences and choose the node with largest number of predecessors.
Climb the aliquot trees on thickest branches (see A135244 = Climb the aliquot trees on shortest paths).
LINKS
W. Creyaufmueller, Aliquot sequences
J. O. M. Pedersen, Tables of Aliquot Cycles [Broken link]
J. O. M. Pedersen, Tables of Aliquot Cycles [Via Internet Archive Wayback-Machine]
J. O. M. Pedersen, Tables of Aliquot Cycles [Cached copy, pdf file only]
Eric Weisstein's World of Mathematics, Aliquot sequence
EXAMPLE
a(25) = 143 since 25 has 3 predecessors (95,119,143) with degrees (4,5,7), 143 having the largest degree. a(5) = 0 since it has no predecessors (see Untouchables - A005114).
KEYWORD
nonn
AUTHOR
Ophir Spector, ospectoro (AT) yahoo.com, Nov 25 2007
STATUS
approved