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A062390
Numbers k such that (k + R(k)) / (k - R(k)) = +-11 where R(k) is the digit reversal of k (A004086).
1
45, 54, 495, 594, 4545, 4995, 5454, 5994, 45045, 49995, 54054, 59994, 450045, 454545, 495495, 499995, 540054, 545454, 594594, 599994, 4500045, 4549545, 4950495, 4999995, 5400054, 5459454, 5940594, 5999994, 45000045, 45045045
OFFSET
1,1
COMMENTS
Are there numbers for which (k + R(k)) / (k - R(k)) is a number other than 11?
LINKS
EXAMPLE
(5994 + 4995) /(5994 - 4995) = 10989/999 = 11, so 5994 is in the sequence.
MATHEMATICA
dr11Q[n_]:=Module[{dr=FromDigits[Reverse[IntegerDigits[n]]]}, n!=dr && Abs[(n+dr)/(n-dr)]==11]; Select[Range[45100000], dr11Q] (* Harvey P. Dale, Oct 03 2011 *)
PROG
(PARI) { n=0; for (m=1, 10^9, x=m; r=0; while (x>0, d=x-10*(x\10); x\=10; r=r*10 + d); if ((m + r) == 11*abs(m - r), write("b062390.txt", n++, " ", m); if (n==44, break)) ) } \\ Harry J. Smith, Aug 07 2009
CROSSREFS
Sequence in context: A044026 A085607 A087993 * A167328 A116247 A168108
KEYWORD
nonn,base,easy
AUTHOR
Amarnath Murthy, Jun 27 2001
EXTENSIONS
Corrected formula and more terms from Jason Earls, Jun 29 2001
Definition corrected and incorrect formula deleted by Harry J. Smith, Aug 06 2009
Missing terms adding like a(5) = 4545 by Harry J. Smith, Aug 07 2009
STATUS
approved