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%I #19 Jul 11 2021 04:44:09
%S 0,8,72,528,4176,32800,262800,2097200,16781472,134218800,1073774880,
%T 8589934672,68719748256,549755813984,4398048608688,35184372156480,
%U 281474993496384,2251799813685376,18014398644225456,144115188075856016
%N a(n) = Sum_{d|n} phi(d)*8^(n/d).
%H Seiichi Manyama, <a href="/A054615/b054615.txt">Table of n, a(n) for n = 0..1000</a>
%F a(n) = Sum_{k=1..n} 8^gcd(n,k). - _Ilya Gutkovskiy_, Apr 16 2021
%o (PARI) a(n) = sumdiv(n, d, eulerphi(d)*8^(n/d)); \\ _Michel Marcus_, Jul 11 2021
%Y Column k=8 of A185651.
%Y Cf. A054627.
%K nonn
%O 0,2
%A _N. J. A. Sloane_, Apr 16 2000