OFFSET
0,3
COMMENTS
a(n) = Phi_22(n) where Phi_k(x) is the k-th cyclotomic polynomial.
LINKS
G. C. Greubel, Table of n, a(n) for n = 0..1000
Eric Weisstein's World of Mathematics, Cyclotomic Polynomial
Index entries for linear recurrences with constant coefficients, signature (11,-55,165,-330,462,-462,330,-165,55,-11,1).
FORMULA
G.f.: (1 - 10*x + 727*x^2 + 36664*x^3 + 389434*x^4 + 1233508*x^5 + 1365310*x^6 + 534568*x^7 + 66661*x^8 + 1926*x^9 + 11*x^10)/(1-x)^11. - Vincenzo Librandi, Feb 29 2016
a(n) = 11*a(n-1) - 55*a(n-2) + 165*a(n-3) - 330*a(n-4) + 462*a(n-5) - 462*a(n-6) + 330*a(n-7) - 165*a(n-8) + 55*a(n-9) - 11*a(n-10) + a(n-11).
Sum_{n>=0} 1/a(n) = 2.0014880486975...
MATHEMATICA
Table[Cyclotomic[22, n], {n, 0, 19}]
CoefficientList[Series[(1 -10x +727x^2 +36664x^3 +389434x^4 +1233508x^5 + 1365310 x^6 +534568x^7 +66661x^8 +1926x^9 +11x^10)/(1-x)^11, {x, 0, 33}], x] (* Vincenzo Librandi, Feb 29 2016 *)
PROG
(PARI) a(n) = polcyclo(22, n); \\ Michel Marcus, Feb 28 2016
(Magma) [n^10-n^9+n^8-n^7+n^6-n^5+n^4-n^3+n^2-n+1: n in [0..30]] // Vincenzo Librandi, Feb 29 2016
(Sage) [sum((-n)^j for j in (0..10)) for n in (0..20)] # G. C. Greubel, Apr 24 2019
(GAP) List([0..20], n-> Sum([0..10], j-> (-n)^j)) # G. C. Greubel, Apr 24 2019
CROSSREFS
KEYWORD
nonn,easy,changed
AUTHOR
Ilya Gutkovskiy, Feb 28 2016
EXTENSIONS
Name changed by G. C. Greubel, Apr 24 2019
STATUS
approved