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A129133
Numbers whose trajectory under the Esucarys map ends at the fixed point 247.
1
247, 1247, 1484, 2473, 4859, 5087, 5738, 7318, 7484, 9563, 9682, 9694, 9938, 11247, 12189, 12473, 14840, 14842, 15209, 15610, 16274, 16563, 16750, 16798, 17609, 19168, 20019, 21885, 24733, 26251, 27123, 27125, 29156, 30076, 30524, 32614, 43899, 44274, 45098, 45787, 48593, 49682, 49694, 49697
OFFSET
1,1
COMMENTS
Old title was: "(c,n) is the n-th number for which the Esucarys sequence starting from it reaches 247 and from there keeps indefinitely this value."
The name "Esucarys" is a reversal of "Syracuse", with the generating rule being that for the Syracuse sequence followed by a reversal.
247 is the only known fixed point of the Esucarys sequence. - Charlie Neder, Jan 12 2019
LINKS
EXAMPLE
For c < 1247 no sequence starting from c except 247 itself reaches 247.
S(1247)=2473, then E(1247) = 3742.
S(3742)=7420, then E(3742) = 247, then (c,1) = 247 and (c,2) = 1247.
CROSSREFS
Sequence in context: A127349 A051153 A166399 * A251265 A001243 A048901
KEYWORD
easy,nonn,base,uned
AUTHOR
Philippe LALLOUET (philip.lallouet(AT)wanadoo.fr), May 25 2007
EXTENSIONS
Extended, missing a(5) and a(6) added, and name changed by Charlie Neder, Jan 12 2019
STATUS
approved