|
|
A230768
|
|
Numbers n such that n = reversal(sigma(n)) - 2.
|
|
1
|
|
|
21, 291, 2991, 43954, 211552, 439954, 880099, 43564354, 43999954, 464057476, 43999999954, 435600004354, 439560043954, 439999999954
(list;
graph;
refs;
listen;
history;
text;
internal format)
|
|
|
OFFSET
|
1,1
|
|
COMMENTS
|
A230021 is a subsequence of this sequence. A term n of this sequence is in the sequence A230021 iff 10 does not divide sigma(n). 880099 is in the sequence and sigma(880099) = 1010880, hence 880099 is not in the sequence A230021. What is the next such term of the sequence?
|
|
LINKS
|
|
|
MATHEMATICA
|
Do[If[n==FromDigits[Reverse[IntegerDigits[DivisorSigma[1, n]]]]-2, Print[n]], {n, 310000000}]
|
|
CROSSREFS
|
|
|
KEYWORD
|
base,nonn
|
|
AUTHOR
|
|
|
EXTENSIONS
|
|
|
STATUS
|
approved
|
|
|
|