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%I #17 Apr 16 2021 15:41:38
%S 0,5,30,135,660,3145,15810,78155,391320,1953405,9768870,48828175,
%T 244157820,1220703185,6103593930,30517584915,152588282640,
%U 762939453205,3814699250430,19073486328215,95367441415140,476837158360185,2384185839844050
%N a(n) = Sum_{d|n} phi(d)*5^(n/d).
%H Seiichi Manyama, <a href="/A054612/b054612.txt">Table of n, a(n) for n = 0..1430</a>
%F a(n) = Sum_{k=1..n} 5^gcd(n,k). - _Ilya Gutkovskiy_, Apr 16 2021
%o (PARI) a(n) = if (n, sumdiv(n, d, eulerphi(d)*5^(n/d)), 0); \\ _Michel Marcus_, Apr 16 2021
%Y Column k=5 of A185651.
%Y Cf. A001869.
%K nonn
%O 0,2
%A _N. J. A. Sloane_, Apr 16 2000
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