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A029985
Squares which are palindromes in base 3.
15
0, 1, 4, 16, 100, 121, 400, 484, 784, 1156, 3136, 6724, 7921, 12769, 23716, 26896, 59536, 68644, 238144, 274576, 532900, 570025, 643204, 743044, 1042441, 1800964, 1844164, 2131600, 4787344, 5026564, 7203856, 7376656, 9278116
OFFSET
1,3
LINKS
Patrick De Geest, Palindromic Squares
G. J. Simmons, On palindromic squares of non-palindromic numbers, J. Rec. Math., 5 (No. 1, 1972), 11-19. [Annotated scanned copy]
MATHEMATICA
b3pQ[n_]:=Module[{idn3=IntegerDigits[n, 3]}, idn3==Reverse[idn3]]; Select[ Range[0, 3200]^2, b3pQ] (* Harvey P. Dale, Aug 07 2011 *)
CROSSREFS
KEYWORD
nonn,base
STATUS
approved