A090200 a(n) = N(7,n), where N(7,x) is the 7th Narayana polynomial.

1, 429, 4279, 20071, 65445, 171481, 387739, 788019, 1476841, 2596645, 4335711, 6936799, 10706509, 16025361, 23358595, 33267691, 46422609, 63614749, 85770631, 113966295, 149442421, 193620169, 248117739, 314767651

Offset: 0

Author

Philippe Deléham, Jan 22 2004

Keywords

• nonn
• easy

Links

• G. C. Greubel, Table of n, a(n) for n = 0..1000
• Index entries for linear recurrences with constant coefficients, signature (7,-21,35,-35,21,-7,1).

Crossrefs

Cf. A001263, A008550, A090198, A090199.

Programs

Magma

[n^6+21*n^5+105*n^4+175*n^3+105*n^2+21*n+1: n in [0..30]]; // G. C. Greubel, Feb 16 2021

Maple

A090200:= n-> n^6+21*n^5+105*n^4+175*n^3+105*n^2+21*n+1; seq(A090200(n), n=0..30) # G. C. Greubel, Feb 16 2021

Mathematica

LinearRecurrence[{7,-21,35,-35,21,-7,1},{1,429,4279,20071,65445,171481,387739},30] (* Harvey P. Dale, Feb 10 2019 *)

PARI

a(n) = n^6+21*n^5+105*n^4+175*n^3+105*n^2+21*n+1 \\ Charles R Greathouse IV, Jan 17 2012

Sage

[n^6+21*n^5+105*n^4+175*n^3+105*n^2+21*n+1 for n in (0..30)] # G. C. Greubel, Feb 16 2021

Formula

a(n) = N(7, n) = Sum_{k>0} A001263(7, k)*n^(k-1) = n^6 + 21*n^5 + 105*n^4 + 175*n^3 + 105*n^2 + 21*n + 1.

G.f.: (1 +422*x +1297*x^2 -908*x^3 -173*x^4 +86*x^5 -5*x^6)/(1-x)^7. - Philippe Deléham, Apr 03 2013; corrected by Georg Fischer, May 02 2019

E.g.f.: (1 +428*x +1711*x^2 +1420*x^3 +380*x^4 +36*x^5 +x^6)*exp(x). - G. C. Greubel, Feb 16 2021

Extensions

Corrected by T. D. Noe, Nov 09 2006