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Numbers k such that k + sigma(k) and k + phi(k) are palindromes.
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%I #13 Jul 15 2021 20:39:02

%S 1,2,3,4,5,219,322,375,22248,32065,47827,1406744,2144055,2991368,

%T 3626587,4909369,172133971,177457001,328030055,3128669654,8345867631,

%U 19649249526,45179367929,47228405729,48534773039,49583585599,2127577449846,2191781701563,3972961263797

%N Numbers k such that k + sigma(k) and k + phi(k) are palindromes.

%C Intersection of A115895 and A115896.

%C a(27) > 10^11. 3972961263797 is also a term. - _Donovan Johnson_, May 31 2013

%C a(30) > 10^13. - _Giovanni Resta_, Jun 05 2013

%e 4909369 + sigma(4909369) = 9823289 and 4909369 + phi(4909369) = 9814189.

%Y Cf. A115895, A115896.

%K nonn,base

%O 1,2

%A _Giovanni Resta_, Feb 06 2006

%E a(17)-a(26) from _Donovan Johnson_, Oct 05 2010

%E a(27)-a(29) from _Giovanni Resta_, Jun 05 2013