A060883 a(n) = n^6 + n^3 + 1.

1, 3, 73, 757, 4161, 15751, 46873, 117993, 262657, 532171, 1001001, 1772893, 2987713, 4829007, 7532281, 11394001, 16781313, 24142483, 34018057, 47052741, 64008001, 85775383, 113390553, 148048057, 191116801, 244156251, 308933353

Offset: 0

Author

N. J. A. Sloane, May 05 2001

Keywords

• nonn
• easy

Comments

a(n) = Phi_9(n) where Phi_k is the k-th cyclotomic polynomial.

Links

• Harry J. Smith, Table of n, a(n) for n = 0..1000
• Index to values of cyclotomic polynomials of integer argument
• Index entries for linear recurrences with constant coefficients, signature (7,-21,35,-35,21,-7,1).

Programs

Maple

A060883 := proc(n)
        numtheory[cyclotomic](9,n) ;
end proc:
seq(A060883(n),n=0..20) ; # R. J. Mathar, Feb 07 2014

Mathematica

Table[n^6+n^3+1,{n,0,30}] (* or *) LinearRecurrence[{7,-21,35,-35,21,-7,1},{1,3,73,757,4161,15751,46873},30] (* Harvey P. Dale, Jul 07 2019 *)

PARI

a(n)={n^6 + n^3 + 1} \\ Harry J. Smith, Jul 13 2009

Formula

G.f.: (1-4*x+73*x^2+274*x^3+325*x^4+50*x^5+x^6)/(1-x)^7. [Colin Barker, Apr 21 2012]