cp's OEIS Frontend

This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

A087994 Integer values of quotients arising in A087993. The quotient is (n+rev(n))/abs(n-rev(n)).

Original entry on oeis.org

11, 11, 11, 11, 5, 11, 11, 11, 132, 132, 11, 5, 19, 37, 37, 55, 55, 73, 73, 5, 11, 91, 11, 91, 11, 11, 5, 67, 67, 12, 12, 19, 37, 37, 55, 55, 73, 73, 5, 11, 11, 91, 11, 11, 91, 22, 44, 132, 11, 110, 132, 11, 44, 110, 4, 22, 109, 11, 11, 109, 5, 127, 127, 145, 145, 163, 163, 4
Offset: 1

Views

Author

Labos Elemer, Oct 08 2003

Keywords

Examples

			n=45, rev(n)=54, q=99/9=9 integer;
n=934065, rev(n)=560434, q=1494504/373626=4
Values observed as quotients:
11,5,132,19,37,55,73,91,67,12,55,22,44,110,4,109,127,163,
		

Crossrefs

Cf. A087993.

Programs

  • Mathematica
    rev[n_] := FromDigits@ Reverse@ IntegerDigits@ n;
    Reap[Do[r=rev@n; If[n != r && IntegerQ[q = (n+r)/(n-r)], Sow@ Abs@ q], {n, 5*^5}]][[2, 1]]