

A281909


Smallest k such that k^i  1 is a totient number (A002202) for all i = 1 to n, or 0 if no such k exists.


2



2, 3, 7, 7, 25, 25, 49, 49, 49, 49, 49, 49, 81, 81, 81, 81, 241, 241, 289, 289, 289, 289, 289, 289, 289, 289, 289, 289, 289, 289, 721, 721, 721, 721, 721, 721, 961, 961, 961, 961, 961, 961
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OFFSET

1,1


LINKS

Table of n, a(n) for n=1..42.


EXAMPLE

a(3) = 7 because 7  1 = 6, 7^2  1 = 48, 7^3  1 = 342 are all totient numbers and 7 is the least number with this property.


CROSSREFS

Cf. A000010, A002202, A045542.
Sequence in context: A027672 A322138 A104138 * A083809 A092967 A056431
Adjacent sequences: A281906 A281907 A281908 * A281910 A281911 A281912


KEYWORD

nonn,more


AUTHOR

Altug Alkan, Feb 01 2017


EXTENSIONS

a(18)a(42) from Max Alekseyev, Feb 07 2017, Mar 06 2017


STATUS

approved



