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Base 5 numbers whose square is a palindrome in base 5.
2

%I #14 Aug 16 2022 16:08:36

%S 0,1,2,11,101,111,231,1001,1111,10001,10101,11011,11204,100001,101101,

%T 110011,242204,1000001,1001001,1010101,1042214,1100011,2020303,

%U 2043122,2443304,10000001,10011001,10100101,11000011,100000001,100010001,100101001,101000101,110000011,111103411

%N Base 5 numbers whose square is a palindrome in base 5.

%C A029988 expressed in base 5.

%H G. J. Simmons, <a href="/A002778/a002778.pdf">On palindromic squares of non-palindromic numbers</a>, J. Rec. Math., 5 (No. 1, 1972), 11-19. [Annotated scanned copy]

%F a(n) = A007091(A029988(n)).

%t With[{b = 5}, FromDigits@ IntegerDigits[#, b] & /@ Select[Range[b^9], PalindromeQ[IntegerDigits[#^2, b]] &]] (* _Michael De Vlieger_, Aug 15 2022 *)

%Y Cf. A007091, A002778, A029988, A263612, A029989.

%K nonn,base

%O 1,3

%A _N. J. A. Sloane_, Oct 23 2015

%E Name corrected by _Charles R Greathouse IV_, Aug 15 2022