cp's OEIS Frontend

This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

A046231 Numbers whose cube is palindromic in base 4.

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%I A046231 #35 Dec 03 2024 20:07:21
%S A046231 0,1,5,17,65,257,1025,4097,16385,65537,262145,1048577,4194305,
%T A046231 16777217,67108865,268435457,1073741825,4294967297
%N A046231 Numbers whose cube is palindromic in base 4.
%C A046231 No number less than 10^8 has a cube that is palindromic in base 2 or base 3.
%C A046231 Next term exceeds 10000000000. - Sam Handler (sam_5_5_5_0(AT)yahoo.com), Aug 09 2006
%H A046231 Patrick De Geest, <a href="https://www.worldofnumbers.com/nobase10pg4.htm">World!Of Numbers</a>, Palindromic cubes in bases 2 to 17.
%F A046231 It seems that for n>=2, a(n)=4^(n-1)+1. - _Benoit Cloitre_, Dec 07 2003
%t A046231 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 *)
%o A046231 (PARI) isok(k) = my(d=digits(k^3,4)); Vecrev(d) == d; \\ _Michel Marcus_, Aug 02 2022
%o A046231 (Python)
%o A046231 from itertools import count, islice
%o A046231 from sympy.ntheory import is_palindromic as ispal
%o A046231 def agen(startk=0): yield from (k for k in count(startk) if ispal(k**3, 4))
%o A046231 print(list(islice(agen(), 12))) # _Michael S. Branicky_, Aug 02 2022
%Y A046231 Cf. A046232.
%Y A046231 Cf. A052539. - _R. J. Mathar_, Oct 13 2008
%K A046231 nonn,more,base
%O A046231 1,3
%A A046231 _Patrick De Geest_, May 15 1998
%E A046231 More terms from Sam Handler (sam_5_5_5_0(AT)yahoo.com), Aug 09 2006, corrected Nov 01 2006