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A269542
Aliquot sequence starting at 702.
2
702, 978, 990, 1818, 2160, 5280, 12864, 21680, 28912, 31848, 47832, 71808, 148512, 359520, 946848, 1895712, 4539360, 12180336, 23781648, 44267568, 76111632, 139130668, 104348008, 92030552, 80526748, 62286692, 55099864, 51042536, 47249404, 35492780, 39042100
OFFSET
0,1
COMMENTS
This sequence is one of the first ones that contains numbers that exceed 2^64 and yet is known to terminate in a small prime followed by 1 and 0.
Note how all the numbers in the sequence are even, except the last 6 (not counting 0).
REFERENCES
R. K. Guy, Unsolved Problems in Number Theory, B6.
Enoch Haga, Exploring Prime Numbers on Your PC, 2nd ed., 1998, pages 83-84 and Table 8, page 46. ISBN 1-885794-16-9.
LINKS
FORMULA
a(n+1) = A001065(a(n)). - R. J. Mathar, Oct 11 2017
MATHEMATICA
NestWhileList[DivisorSigma[1, #]-#&, 702, #>0&] (* Paolo Xausa, Oct 16 2023 *)
PROG
(PARI) lista() = {print1(a=702, ", "); until (!a, a = sigma(a) - a; print1(a, ", "); ); } \\ Michel Marcus, Feb 29 2016
CROSSREFS
Sequence in context: A252574 A252575 A252566 * A237632 A304155 A305508
KEYWORD
nonn,fini,full
AUTHOR
Daniel Mondot, Feb 29 2016
STATUS
approved