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.

A083114 Numbers with nonzero digits whose sum of digits as well as product of digits is a palindrome.

Original entry on oeis.org

1, 2, 3, 4, 5, 6, 7, 8, 9, 11, 12, 13, 14, 15, 16, 17, 18, 21, 22, 23, 24, 31, 32, 33, 41, 42, 51, 61, 71, 81, 111, 112, 113, 114, 115, 116, 117, 119, 121, 122, 123, 124, 131, 132, 133, 141, 142, 151, 161, 171, 191, 211, 212, 213, 214, 221, 222, 231, 241
Offset: 1

Views

Author

Amarnath Murthy, Apr 23 2003

Keywords

Crossrefs

Cf. A083115.

Programs

  • Mathematica
    id[n_]:=IntegerDigits[n]; palQ[n_]:=Reverse[x=id[n]]==x; t={}; Do[If[(y=Times@@id[n])>0 && palQ[Plus@@id[n]] && palQ[y],AppendTo[t,n]],{n,222}]; t (* Jayanta Basu, May 15 2013 *)
    Select[Range[300],FreeQ[IntegerDigits[#],0]&&AllTrue[{Total[IntegerDigits[#]],Times@@ IntegerDigits[ #]},PalindromeQ]&] (* Harvey P. Dale, Mar 25 2024 *)
  • PARI
    ispal(n)=n=digits(n);for(i=1,#n\2,if(n[i]!=n[#n+1-i],return(0)));1
    is(n)=my(d=vecsort(digits(n)));d[1]&&ispal(sum(i=1,#d,d[i]))&&ispal(prod(i=1,#d,d[i])) \\ Charles R Greathouse IV, May 15 2013

Extensions

Corrected by Harvey P. Dale, Mar 25 2024