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.

Showing 1-3 of 3 results.

A027713 Palindromes of form k^2 + k + 2.

Original entry on oeis.org

2, 4, 8, 22, 44, 212, 242, 464, 2552, 8558, 40604, 41414, 85558, 229922, 805508, 2029202, 2342432, 2737372, 4006004, 4437344, 4767674, 281585182, 400060004, 440727044, 805282508, 8059999508, 40000600004, 47997579974, 251476674152, 2626540456262, 2728292928272
Offset: 1

Views

Author

Keywords

Comments

Palindromes h such that 4*h - 7 is a square. - Bruno Berselli, Aug 29 2018

Crossrefs

Programs

  • Magma
    [m: n in [0..10^7] | Intseq(m) eq Reverse(Intseq(m)) where m is n^2+n+2]; // Vincenzo Librandi, Mar 27 2011
  • Mathematica
    palQ[n_] := Module[{idn = IntegerDigits[n]}, idn == Reverse[idn]]; Select[Table[n^2 + n + 2, {n, 0, 502000}], palQ] (* Harvey P. Dale, Sep 15 2011 *)

Extensions

More terms from Giovanni Resta, Aug 28 2018

A027714 Numbers k such that k^2+k+3 is a palindrome.

Original entry on oeis.org

0, 1, 2, 5, 19, 23, 60, 71, 175, 179, 184, 243, 753, 2431, 6154, 23111, 30947, 73188, 75146, 230663, 237721, 598350, 3093852, 5492899, 17605724, 18886025, 30909092, 62127180, 76675186, 177865385, 230098566, 309230287, 549199524, 589167859, 726714741
Offset: 1

Views

Author

Keywords

Crossrefs

Programs

  • Mathematica
    npalQ[n_]:=Module[{c=n^2+n+3},c==IntegerReverse[c]]; Select[Range[ 0,31*10^5],npalQ] (* Requires Mathematica version 10 or later *) (* Harvey P. Dale, Aug 15 2016 *)

Extensions

More terms from Giovanni Resta, Aug 29 2018

A028413 Numbers k such that k^2 + k + 1 is a palindrome.

Original entry on oeis.org

0, 1, 2, 10, 18, 27, 100, 125, 173, 1000, 1120, 1184, 1355, 1836, 1876, 1961, 10000, 11915, 100000, 119084, 126935, 187876, 188348, 192383, 196813, 1000000, 1010200, 1190915, 1228425, 1780728, 1821636, 1975356, 10000000, 11842184, 12643549, 12783239, 18016058
Offset: 1

Views

Author

Keywords

Crossrefs

Programs

  • Mathematica
    palQ[n_] := Block[{d = IntegerDigits[n]}, d == Reverse[d]]; f[n_] := n^2 + n + 1; Select[Range[0, 10^5], palQ@ f@ # &] (* Giovanni Resta, Aug 29 2018 *)

Extensions

More terms from Giovanni Resta, Aug 28 2018
Showing 1-3 of 3 results.