0,2

The initial terms coincide with those of A170741, although the two sequences are eventually different.

Computed with Magma using commands similar to those used to compute A154638.

G. C. Greubel, Table of n, a(n) for n = 0..500

Index entries for linear recurrences with constant coefficients, signature (20,20,20,20,20,20,20,20,20,-210).

G.f.: (t^10 + 2*t^9 + 2*t^8 + 2*t^7 + 2*t^6 + 2*t^5 + 2*t^4 + 2*t^3 + 2*t^2 + 2*t + 1)/(210*t^10 - 20*t^9 - 20*t^8 - 20*t^7 - 20*t^6 - 20*t^5 - 20*t^4 - 20*t^3 - 20*t^2 - 20*t + 1).

seq(coeff(series((1+t)*(1-t^10)/(1-21*t+230*t^10-210*t^11), t, n+1), t, n), n = 0..20); # G. C. Greubel, Sep 25 2019

CoefficientList[Series[(1+t)*(1-t^10)/(1-21*t+230*t^10-210*t^11), {t, 0, 25}], t] (* G. C. Greubel, Apr 17 2016 *)

coxG[{10, 210, -20}] (* The coxG program is at A169452 *) (* G. C. Greubel, Sep 25 2019 *)

(PARI) my(t='t+O('t^20)); Vec((1+t)*(1-t^10)/(1-21*t+230*t^10-210*t^11)) \\ G. C. Greubel, Sep 25 2019

(Magma) R<t>:=PowerSeriesRing(Integers(), 20); Coefficients(R!( (1+t)*(1-t^10)/(1-21*t+230*t^10-210*t^11) )); // G. C. Greubel, Sep 25 2019

(SageMath)

def A165895_list(prec):

P.<t> = PowerSeriesRing(ZZ, prec)

return P((1+t)*(1-t^10)/(1-21*t+230*t^10-210*t^11)).list()

A165895_list(20) # G. C. Greubel, Sep 25 2019

(GAP) a:=[22, 462, 9702, 203742, 4278582, 89850222, 1886854662, 39623947902, 832102905942, 17474161024551];; for n in [11..25] do a[n]:=20*Sum([1..9], j-> a[n-j]) -210*a[n-10]; od; Concatenation([1], a); # G. C. Greubel, Sep 25 2019

Cf. A154638, A170741.

Sequence in context: A164635 A164956 A165364 * A166416 A166608 A167075

Adjacent sequences: A165892 A165893 A165894 * A165896 A165897 A165898

John Cannon and N. J. A. Sloane, Dec 03 2009

approved