

A057135


Palindromes whose square is a palindrome; also palindromes whose sum of squares of digits is less than 10.


7



0, 1, 2, 3, 11, 22, 101, 111, 121, 202, 212, 1001, 1111, 2002, 10001, 10101, 10201, 11011, 11111, 11211, 20002, 20102, 100001, 101101, 110011, 111111, 200002, 1000001, 1001001, 1002001, 1010101, 1011101, 1012101, 1100011, 1101011, 1102011, 1110111, 1111111
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OFFSET

1,3


COMMENTS

Needs longer bfile  N. J. A. Sloane, Dec 18 2015.


LINKS

R. J. Mathar, Table of n, a(n) for n = 1..412
P. De Geest, Subsets of Palindromic Squares


FORMULA

a(n) = sqrt(A057136(n))


EXAMPLE

121 is OK since 121^2=14641 is also a palindrome.


MATHEMATICA

PalQ[n_] := FromDigits[Reverse[IntegerDigits[n]]] == n; t = {}; Do[
If[PalQ[n] && PalQ[n^2], AppendTo[t, n]], {n, 0, 1200000}]; t (* Jayanta Basu, May 10 2013 *)


CROSSREFS

Cf. A000290, A002113, A002779, A057136, A128921.
Sequence in context: A229549 A229804 A241096 * A229805 A104075 A236168
Adjacent sequences: A057132 A057133 A057134 * A057136 A057137 A057138


KEYWORD

base,nonn


AUTHOR

Henry Bottomley, Aug 12 2000


EXTENSIONS

1001001 inserted by R. J. Mathar, Nov 04 2012


STATUS

approved



