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%I #17 Oct 16 2021 12:23:53
%S 0,1,2,7,37,43,76,91,217,259,1064,1297,1333,1519,1555,2704,3367,7777,
%T 8029,9079,19747,46657,46873,47989,48205,54439,54655,54695,83979,
%U 118027,241304,279937,281449,287749,326599,707707,1679617
%N Numbers k such that k^2 is palindromic in base 6.
%H Seiichi Manyama, <a href="/A029990/b029990.txt">Table of n, a(n) for n = 1..92</a>
%H Patrick De Geest, <a href="http://www.worldofnumbers.com/square.htm">Palindromic Squares</a>
%t palindromicQ[n_, b_:10] := TrueQ[IntegerDigits[n, b] == Reverse[IntegerDigits[n, b]]]; Select[Range[1000], palindromicQ[#^2, 6] &] (* _Alonso del Arte_, Mar 05 2017 *)
%o (PARI) ispal(n,base)=my(d=digits(n,base)); d==Vecrev(d)
%o is(n)==ispal(n^2,6) \\ _Charles R Greathouse IV_, Mar 09 2017
%Y Cf. A007092.
%Y Numbers k such that k^2 is palindromic in base b: A003166 (b=2), A029984 (b=3), A029986 (b=4), A029988 (b=5), this sequence (b=6), A029992 (b=7), A029805 (b=8), A029994 (b=9), A002778 (b=10), A029996 (b=11), A029737 (b=12), A029998 (b=13), A030072 (b=14), A030073 (b=15), A029733 (b=16), A118651 (b=17).
%K nonn,base
%O 1,3
%A _Patrick De Geest_