

A192219


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.


0



1226221, 13488431, 123848321, 12467976421, 1030507050301, 1120237320211, 1225559555221, 1234469644321, 1334459544331, 11335577553311, 100330272033001, 101222252222101, 103023070320301, 113143969341311, 121363494363121, 134312696213431
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OFFSET

1,1


COMMENTS

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.


LINKS

Table of n, a(n) for n=1..16.


EXAMPLE

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.


MATHEMATICA

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 *)


CROSSREFS

Sequence in context: A257159 A254741 A203259 * A282424 A129347 A071146
Adjacent sequences: A192216 A192217 A192218 * A192220 A192221 A192222


KEYWORD

nonn,base


AUTHOR

Jaroslav Krizek, Jul 13 2011


EXTENSIONS

a(5)a(16) (including six found by T. D. Noe) from Donovan Johnson, Jul 14 2011


STATUS

approved



