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A027579
Numbers n such that n^2 + (n+1)^2 + (n+2)^2 + (n+3)^2 + (n+4)^2 is palindromic.
1
1, 99, 331, 3207, 10099, 105720053635, 10310949321253
OFFSET
1,2
COMMENTS
All terms are odd. - Chai Wah Wu, Jan 18 2016
MATHEMATICA
Select[Range[15000], PalindromeQ[5(6+4#+#^2)]&] (* The program uses the PalindromeQ function from Mathematica version 10.3 *) (* Harvey P. Dale, Nov 02 2015 *)
PROG
(PARI) isok(n) = my(d = digits(n^2 + (n+1)^2 + (n+2)^2 + (n+3)^2 + (n+4)^2)); d == Vecrev(d); \\ Michel Marcus, Jan 24 2016
CROSSREFS
Cf. A027580.
Sequence in context: A008902 A008882 A156757 * A304675 A316122 A157659
KEYWORD
nonn,base,more
EXTENSIONS
a(6) from Chai Wah Wu, Jan 18 2016
a(7) from Giovanni Resta, Aug 04 2019
STATUS
approved