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A046231
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Numbers whose cube is palindromic in base 4.
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2
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0, 1, 5, 17, 65, 257, 1025, 4097, 16385, 65537, 262145, 1048577, 4194305, 16777217, 67108865, 268435457, 1073741825, 4294967297
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OFFSET
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1,3
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COMMENTS
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No number less than 10^8 has a cube that is palindromic in base 2 or base 3.
Next term exceeds 10000000000. - Sam Handler (sam_5_5_5_0(AT)yahoo.com), Aug 09 2006
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LINKS
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FORMULA
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MATHEMATICA
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For[i = 1, i < 1000000, i++, tmp = IntegerDigits[i^3, 4]; If[tmp == Reverse[tmp], Print[i]] ]; (* Sam Handler (sam_5_5_5_0(AT)yahoo.com), Aug 09 2006 *)
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PROG
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(PARI) isok(k) = my(d=digits(k^3, 4)); Vecrev(d) == d; \\ Michel Marcus, Aug 02 2022
(Python)
from itertools import count, islice
from sympy.ntheory import is_palindromic as ispal
def agen(startk=0): yield from (k for k in count(startk) if ispal(k**3, 4))
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CROSSREFS
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KEYWORD
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nonn,more,base
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AUTHOR
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EXTENSIONS
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More terms from Sam Handler (sam_5_5_5_0(AT)yahoo.com), Aug 09 2006, corrected Nov 01 2006
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STATUS
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approved
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