A054615 a(n) = Sum_{d|n} phi(d)*8^(n/d).

0, 8, 72, 528, 4176, 32800, 262800, 2097200, 16781472, 134218800, 1073774880, 8589934672, 68719748256, 549755813984, 4398048608688, 35184372156480, 281474993496384, 2251799813685376, 18014398644225456, 144115188075856016

Offset

0,2

Links

Seiichi Manyama, Table of n, a(n) for n = 0..1000

Formula

a(n) = Sum_{k=1..n} 8^gcd(n,k). - Ilya Gutkovskiy, Apr 16 2021

Prog

(PARI) a(n) = sumdiv(n, d, eulerphi(d)*8^(n/d)); \\ Michel Marcus, Jul 11 2021

Crossrefs

Column k=8 of A185651.

Cf. A054627.

Sequence in context: A082141 A304826 A270241 * A344067 A111919 A052379

Adjacent sequences: A054612 A054613 A054614 * A054616 A054617 A054618

Keyword

nonn

Author

N. J. A. Sloane, Apr 16 2000

Status

approved