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A054608
a(n) = Sum_{d|9} phi(d)*n^(9/d).
2
0, 9, 540, 19755, 262296, 1953405, 10078164, 40354335, 134218800, 387422001, 1000002060, 2357950419, 5159783880, 10604503845, 20661052356, 38443366215, 68719485024, 118587886425, 198359302140, 322687711611, 512000016120
OFFSET
0,2
LINKS
Index entries for linear recurrences with constant coefficients, signature (10,-45,120,-210,252,-210,120,-45,10,-1).
FORMULA
G.f.: 9*x*(x^8 + 50*x^7 + 1640*x^6 + 9774*x^5 + 17390*x^4 + 9774*x^3 + 1640*x^2 + 50*x + 1) / (x - 1)^10. - Colin Barker, Dec 21 2012
a(n) = n^9 + 2*n^3 + 6*n. - Seiichi Manyama, Jul 11 2021
PROG
(PARI) a(n) = n^9+2*n^3+6*n; \\ Seiichi Manyama, Jul 11 2021
CROSSREFS
Row n=9 of A185651.
Sequence in context: A015508 A281800 A266889 * A269661 A287043 A317347
KEYWORD
nonn,easy
AUTHOR
N. J. A. Sloane, Apr 16 2000
STATUS
approved