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.

A117055 Palindromes for which the product of the digits is also a palindrome.

Original entry on oeis.org

0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 11, 22, 33, 101, 111, 121, 131, 141, 151, 161, 171, 181, 191, 202, 212, 222, 303, 313, 404, 505, 606, 676, 707, 777, 808, 909, 1001, 1111, 1221, 1331, 2002, 2112, 3003, 3113, 4004, 5005, 6006, 7007, 8008, 9009, 10001, 10101
Offset: 1

Views

Author

Luc Stevens (lms022(AT)yahoo.com), Apr 16 2006

Keywords

Examples

			676 is in the sequence because it is a palindrome and the product of its digits 6*7*6=252 is also a palindrome.
		

Crossrefs

Programs

  • Magma
    f:=func; [k:k in [0..10000]| f(k) and f(&*Intseq(k))]; // Marius A. Burtea, Nov 11 2019
  • Mathematica
    id[n_]:=IntegerDigits[n]; palQ[n_]:=Reverse[x=id[n]]==x; t={}; Do[If[palQ[n] && palQ[Times@@id[n]],AppendTo[t,n]],{n,0,10110}]; t (* Jayanta Basu, May 15 2013 *)
  • PARI
    isok(n) = my(d = digits(n), dp = digits(vecprod(d))); (Vecrev(d) == d) && (Vecrev(dp) == dp); \\ Michel Marcus, Nov 11 2019