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A115900
Numbers k such that k + sigma(k) and k + phi(k) are palindromes.
0
1, 2, 3, 4, 5, 219, 322, 375, 22248, 32065, 47827, 1406744, 2144055, 2991368, 3626587, 4909369, 172133971, 177457001, 328030055, 3128669654, 8345867631, 19649249526, 45179367929, 47228405729, 48534773039, 49583585599, 2127577449846, 2191781701563, 3972961263797
OFFSET
1,2
COMMENTS
Intersection of A115895 and A115896.
a(27) > 10^11. 3972961263797 is also a term. - Donovan Johnson, May 31 2013
a(30) > 10^13. - Giovanni Resta, Jun 05 2013
EXAMPLE
4909369 + sigma(4909369) = 9823289 and 4909369 + phi(4909369) = 9814189.
CROSSREFS
Sequence in context: A274028 A037436 A377073 * A349486 A010347 A004878
KEYWORD
nonn,base
AUTHOR
Giovanni Resta, Feb 06 2006
EXTENSIONS
a(17)-a(26) from Donovan Johnson, Oct 05 2010
a(27)-a(29) from Giovanni Resta, Jun 05 2013
STATUS
approved