A059744 Numbers k such that k^2 is a palindromic square of sporadic type.

26, 264, 307, 836, 2285, 2636, 22865, 24846, 30693, 798644, 1042151, 1270869, 2012748, 2294675, 3069307, 11129361, 12028229, 12866669, 30001253, 64030648, 306930693, 2062386218, 2481623254, 10106064399, 10207355549, 13579355059, 22865150135, 30101273647, 30693069307

Offset: 1

Author

N. J. A. Sloane, Feb 21 2001

Keywords

• nonn
• base

References

• C. Ashbacher, More on palindromic squares, J. Rec. Math. 22, no. 2 (1990), 133-135. [A scan of the first page of this article is included with the last page of the Keith (1990) scan]
• J. K. R. Barnett, "Tables of Square Palindromes in Bases 2 and 10," Journal of Recreational Mathematics, 23:1, pp. 13-18, 1991.
• J.-M. De Koninck, Ces nombres qui nous fascinent, Entry 26, pp 10, Ellipses, Paris 2008.
• M. Keith, "Classification and Enumeration of Palindromic Squares," Journal of Recreational Mathematics, 22:2, pp. 124-132, 1990.
• R. Ondrejka, "A Palindrome (151) of Palindromic Squares," Journal of Recreational Mathematics, 20:1, pp. 68-71, 1988.

Links

• Patrick De Geest, Full List of the Sporadic Square Palindromes (SSP), part of Palindromic Squares website on WorldOfNumbers.
• M. Keith, Classification and enumeration of palindromic squares, J. Rec. Math., 22 (No. 2, 1990), 124-132. [Annotated scanned copy] (Has ten more terms)
• W. R. Marshall, Table up to 10^20

Crossrefs

Cf. A059745, A016106, A028818, A060087.

Programs

Mathematica

Select[Range[1042151], ! PalindromeQ[#] && PalindromeQ[#^2] &] (* Michael De Vlieger, Oct 03 2023, not suitable for terms > 1042151, needs amendment for larger terms *)

Extensions

More terms from WorldOfNumbers website, communicated by Hugo Pfoertner, Oct 03 2023