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A027713 Palindromes of form k^2 + k + 2. 5
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 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,1
COMMENTS
Palindromes h such that 4*h - 7 is a square. - Bruno Berselli, Aug 29 2018
LINKS
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 *)
PROG
(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
CROSSREFS
Sequence in context: A115778 A333016 A295628 * A155765 A217975 A027385
KEYWORD
nonn,base
AUTHOR
EXTENSIONS
More terms from Giovanni Resta, Aug 28 2018
STATUS
approved

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Last modified April 18 22:18 EDT 2024. Contains 371782 sequences. (Running on oeis4.)