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A192219
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Numbers m such that set of divisors of m is equal to set of reversals of divisors of m but all divisors of m are not palindromic.
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0
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1226221, 13488431, 123848321, 12467976421, 1030507050301, 1120237320211, 1225559555221, 1234469644321, 1334459544331, 11335577553311, 100330272033001, 101222252222101, 103023070320301, 113143969341311, 121363494363121, 134312696213431
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OFFSET
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1,1
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COMMENTS
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All terms are palindromic (subsequence of A002113 - palindromic numbers).
Subsequence of A188650 (numbers that are divisible by all reversals of their divisors).
Union a(n) and A062687 (numbers all of whose divisors are palindromic) is sequence of numbers m such that set of divisors of m is equal to set of reversals of divisors of m: {1, 2, 3, 4, 5, 6, 7, 8, 9, 11, 22, 33, 44, 55, 66, 77, 88, 99, 101, 121, 131, ..., 1226221, ...). - Jaroslav Krizek, Jul 18 2011.
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LINKS
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EXAMPLE
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1226221 has divisors 1, 1021, 1201, 1226221. Set of divisors is equal to set of reversals of divisors. Divisors 1021 and 1201 are not palindromic.
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MATHEMATICA
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t = Union[Flatten[Table[d = IntegerDigits[n]; {FromDigits[Join[d, Reverse[d]]], FromDigits[Join[d, Reverse[Most[d]]]]}, {n, 0, 99999}]]]; okQ[n_] := Module[{f = Divisors[n], r}, r = f; Do[r[[i]] = FromDigits[Reverse[IntegerDigits[f[[i]]]]], {i, Length[f]}]; f == Sort[r] && f != r]; Select[t, okQ] (* T. D. Noe, Jul 14 2011 *)
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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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a(5)-a(16) (including six found by T. D. Noe) from Donovan Johnson, Jul 14 2011
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STATUS
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approved
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