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A216224 Natural growth of an aliquot sequence driven by a perfect number 2^(p-1)*((2^p)-1), but starting at 27. 2
27, 53, 55, 89, 91, 133, 187, 245, 439, 441, 1041, 1743, 3633, 7503, 13329, 25203, 44429, 66547, 76813, 90803, 90805, 167243, 187957, 280907, 332005, 499739, 499741, 600995, 841405, 1177979, 1392181, 1977419, 1992661, 2398187, 3062293, 3600363, 6739253, 7507147 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Quote from the abstract of the article by te Riele: "In this note, the existence of an aliquot sequence with more than 5092 monotonically increasing even terms is proved". The author uses the perfect number corresponding to the Mersenne prime 2^p-1 with p=19937 (whereas the script below only uses p=521).

LINKS

Table of n, a(n) for n=1..38.

H. J. J. te Riele, A note on the Catalan-Dickson conjecture, Math. Comp. 27 (1973), 189-192.

PROG

(PARI) lista(p=521, nb) = {perf = 2^(p-1)*(2^p-1); a = 27*perf; print1(a/perf, ", "); for (i=1, nb, a = sigma(a) - a; print1(a/perf, ", "); if (gcd(a/perf, p) != 1, return()); ); } \\ Michel Marcus, Mar 13 2013

CROSSREFS

Cf. A146556, A215778.

Sequence in context: A044079 A044460 A160845 * A255364 A082915 A183032

Adjacent sequences: A216221 A216222 A216223 * A216225 A216226 A216227

KEYWORD

nonn

AUTHOR

Michel Marcus, Mar 13 2013

STATUS

approved

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Last modified December 8 12:32 EST 2022. Contains 358693 sequences. (Running on oeis4.)