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A087988
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Palindromic numbers whose squares and cubes are equally palindromic.
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0
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0, 1, 2, 11, 101, 111, 1001, 10001, 10101, 11011, 100001, 101101, 110011, 1000001, 1001001, 1100011, 10000001, 10011001, 10100101, 11000011, 100000001, 100010001, 100101001, 101000101, 110000011, 1000000001, 1000110001
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OFFSET
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1,3
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COMMENTS
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Numbers n such that n, n^2 and n^3 are all palindromes.
Essentially A002780 with two terms removed, 7 and 2201.
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LINKS
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EXAMPLE
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11^2=121, 11^3=1331.
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MAPLE
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rev:=proc(a) local aa, ct: aa:=convert(a, base, 10): ct:=nops(aa): add(10^(ct-j)*aa[j], j=1..ct) end: p:=proc(n) if rev(n)=n and rev(n^2)=n^2 and rev(n^3)=n^3 then n else fi end: seq(p(n), n=0..12*10^5); # Emeric Deutsch, May 01 2005
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PROG
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(PARI) ispal(n) = my(d = digits(n)); Vecrev(d) == d;
isok(n) = ispal(n) && ispal(n^2) && ispal(n^3); \\ Michel Marcus, Oct 25 2015
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CROSSREFS
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KEYWORD
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nonn,base
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AUTHOR
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EXTENSIONS
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STATUS
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approved
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