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.

A087988 Palindromic numbers whose squares and cubes are equally palindromic.

Original entry on oeis.org

0, 1, 2, 11, 101, 111, 1001, 10001, 10101, 11011, 100001, 101101, 110011, 1000001, 1001001, 1100011, 10000001, 10011001, 10100101, 11000011, 100000001, 100010001, 100101001, 101000101, 110000011, 1000000001, 1000110001
Offset: 1

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Author

Labos Elemer, Oct 01 2003

Keywords

Comments

Numbers n such that n, n^2 and n^3 are all palindromes.
Essentially A002780 with two terms removed, 7 and 2201.

Examples

			11^2=121, 11^3=1331.
		

Crossrefs

Intersection of A002113, A002778 and A002780.

Programs

  • Maple
    rev:=proc(a) local aa,ct: aa:=convert(a,base,10): ct:=nops(aa): add(10^(ct-j)*aa[j],j=1..ct) end: p:=proc(n) if rev(n)=n and rev(n^2)=n^2 and rev(n^3)=n^3 then n else fi end: seq(p(n),n=0..12*10^5); # Emeric Deutsch, May 01 2005
  • PARI
    ispal(n) = my(d = digits(n)); Vecrev(d) == d;
    isok(n) = ispal(n) && ispal(n^2) && ispal(n^3); \\ Michel Marcus, Oct 25 2015

Extensions

More terms from Ray Chandler, Oct 05 2003
Edited by N. J. A. Sloane, Aug 29 2008 at the suggestion of R. J. Mathar