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

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

Author

Patrick De Geest

Keywords

• nonn
• base

Comments

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

Links

• Giovanni Resta, Table of n, a(n) for n = 1..65
• Patrick De Geest, Palindromic Quasi_Over_Squares of the form n^2+(n+X)

Crossrefs

Cf. A014206, A027712, A028414, A027715.

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