A027579 Numbers n such that n^2 + (n+1)^2 + (n+2)^2 + (n+3)^2 + (n+4)^2 is palindromic.

1, 99, 331, 3207, 10099, 105720053635, 10310949321253

Offset

1,2

Comments

All terms are odd. - Chai Wah Wu, Jan 18 2016

Links

Table of n, a(n) for n=1..7.

P. De Geest, Palindromic Sums of Squares of Consecutive Integers

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

Adjacent sequences: A027576 A027577 A027578 * A027580 A027581 A027582

Keyword

nonn,base,more

Author

Patrick De Geest

Extensions

a(6) from Chai Wah Wu, Jan 18 2016

a(7) from Giovanni Resta, Aug 04 2019

Status

approved